Hard Armor

Hard armor is a term used to describe a body armor plate which has been fabricated in such a way as to form a rigid panel or “plate”. The result, regardless of materials used, directly correlates to a significant increase in the ballistic resistance of the materials used. This effect can be further improved through the use of enhanced materials. 

Hard armor is heavier and more cumbersome than soft armor, however it is required in situations where impact from rifle rounds is a possibility, whereas soft armor is incapable of defeating such projectiles.

Hard armor comes in a variety of levels, with a wide range of physical and mechanical properties as determined by the materials used.

Soft Armor

Soft armor relates to those applications which consist of numerous layers of loosely fit ballistic sheets which have not been formed into a hard plate. Although more flexible than hard armor, soft armor is limited in scope as a result of the lower levels of protection provided and as such is largely obsolete with regards to civilian applications.

There does exist, a number of flexible rifle rated systems but the drawbacks of such systems, such as angular impact vulnerabilities, make them of little importance to this summary.

Materials Used In The Manufacturing Process:

High Density Polyethylene and UHMWPE

Polyethylene fibers have replaced Kevlar in most modern hard armor applications, due to greatly improved ballistic resistance and a significant reduction in weight. This is a result of the dense molecular chains formed when processing UHMWPE fibers, and the fact that dense impregnated resins are no longer required. This makes plates of this type a viable option for those who may have difficulty bearing the load of heavier, Level iV polymer / ceramic plates.

Polyethylene armor systems are manufactured by bonding unidirectional UHMWPE (Ultra High Molecular Weight Polyethylene) fibers over an HDPE (High Density Polyethylene) sheet. The sheets are then placed in a mold which is then placed under heat and pressure, resulting in a cohesive, lightweight hard armor panel which is then cut to shape with a 3 axis waterjet to form a finished plate. 

When struck by a projectile the plate delaminates at the point of impact, distributing the force over a wide area while trapping the round within the plate itself, thereby eliminating spall entirely.

Another interesting attribute of UHMWPE is that it is positively buoyant, meaning that plates comprised solely of this material will float, making them ideal for use in and around water.

Polyethylene can be used independent of other materials to form Level III and III+ plates capable of defeating 5.56, 7.62x39 and .308 rounds, however it cannot stop certain steel core or armor piercing ammunition without the addition of ceramic breaker plates. 

For example, M855 or “greentip” rounds will penetrate a plate comprised entirely of UHMWPE but standard “lead core” 5.56 or .308, as well as 7.62x39 MSC (mild steel core) cannot penetrate high end UHMWPE plates.


A range of ceramics materials are now widely used in combination with Polyethylene based materials in order to provide Level IV protection, capable of defeating armor piercing ammunition. The ceramic overlay is used on the exterior of the Polyethylene plate and acts as what is referred to as a “breaker plate”. The hardness of the ceramic layer causes the projectile to fragment on impact. The Polyethylene material then acts as what is referred to as a “backer plate”, trapping the fragments within the layers of the material through the mechanism of delamination, thus eliminating spall while fragmenting and defeating the projectile.

Ceramic materials come in 3 variations; Alumina Oxide, Silica Carbide and Boron Carbide.

Alumina Oxide is the lowest cost option but has excellent ballistic properties and is extremely resilient against drops and impacts with minimal fracturing on impact.

Silica Carbide is the second most expensive option and can have improved performance against certain less common threats but it tends to fracture on impact more than Alumina Oxide.

Boron Carbide is the pinnacle of ceramic options. It has incredible performance against both ballistic impacts and repeated drops but it tends to be very expensive.

We use Alumina Oxide on most of our plate options with Boron Carbide being made available on our 26300 and 28590 variants. If you want top performance and have the budget to back that choice this is the way to go.

Carbon Nanotubes

Carbon Nanotubes have the potential to provide a quantum leap in ballistic materials as a result of the dense molecular chains of these materials and the geometric shape of the tubes themselves. Hoplite Armor, has been working in conjunction with Dr. Brian Grady, Professor of Chemical Engineering and Materials Science at the University of Oklahoma, in order to develop advanced materials based on the use of Carbon Nanotubes. While these materials hold vast potential, they are, as of yet, not commercially viable for ballistic applications due to excessive cost. As this technology improves and becomes more commonplace, materials costs will be reduced and Carbon Nanotubes will quickly emerge as the primary option for ballistic applications.


Aramid fiber is produced by spinning a solid fiber from a liquid chemical blend. This causes the polymer chains to orientate in the direction of the fiber, increasing strength.  Perhaps the most widely known aramid, Kevlar, was developed by Stephanie Kwolek at DuPont in 1965. This high-strength material was first commercially used in the early 1970’s as a replacement for steel in racing tires and later evolved into a primary component of various ballistic applications. Typically it is spun into ropes or fabric sheets that can be used as such or as an ingredient in composite material components. In modern ballistic applications Kevlar can be seen in both hard and soft armor. It is however heavier and less effective as compared to its modern replacement, UHMWPE, or Ultra High Molecular Weight Polyethylene.


Steel was the first commercially available material used to defeat the penetration of projectiles, starting as early as WWI. However, due to the fact that steel plates are easily penetrated by standard “lead core” 5.56 rounds traveling at a velocity greater than 2,700 fps. Additionally, steel can create excessive spall, which can result in secondary fragmentation injuries. Some manufacturers still provide steel plate products, selling exclusively to civilians, however we DO NOT sell steel plates due to safety concerns as outlined above. Even with the use of “spall resistant” coatings, safety should be a major concern to anyone currently utilizing and relying upon steel plates.

Levels of Protection

The NIJ or National Institute of Justice recognizes 2 Levels with rifle rated protection; Levels III and IV. However, in an effort to create a more specific series of product categories, many body armor manufacturers recognize 2 additional Levels, III+ and III++. While many retailers simplify this to a standard III+ rating, we feel it is important that we provide our customers with a more detailed outline of which plates stop what rounds as well as a summary of weights, sizes, and materials. The following summary and attached product outline provide vital information regarding specific performance standards.

NIJ Level III is designed to stop multiple “lead core” or “ball” variants of the following ammunition

5.56 / .223, 7.62x39 and .308 up to 3,300 fps

Level III+ stops all of the above “plus” 7.62x39 MSC (mild steel core)

Level III++ stops all of the above “plus” M855 and M855A1

Level IV stops all of the above as well as full Armor Piercing rounds up to 30.06 AP (armor piercing).

Plate Cut Styles

The acronym SAPI actually stands for Small Arms Protective Insert, but it has become more widely recognized as a specific cut pattern. Plate cut styles are designated according to the type of relief cut at the top of the plate, which in the case of SAPI plates is roughly 45 degrees. SAPI Plates were the standard cut style in the early days of Hard Armor plates and they are still the primary standard cut style used by the vast majority of people worldwide. SAPI cut plates provide extended coverage but can impede movement, depending on the body type and build of the wearer.

See the link below for a complete listing of our SAPI Plate Collection

SAPI Plates – Hoplite Armor Store


Swimmer Plates are cut with a steeper angle, roughly 60 degrees, and provide a greater range of motion, especially with any movements that require an extended range of arm motion such as holding a pistol with 2 hands, shouldering a weapon, or any other movement that is similar in nature to a breaststroke, hence the term Swimmer Plate. The same motions one would make when swimming are more easily performed when wearing a Swimmer Plate as opposed to a SAPI plate. 

See the link below for a complete listing of our Swimmer Plate Collection

Swimmer Plates – Hoplite Armor Store

The Swimmer SAPI Combo provides the best of both worlds, by maximizing the agility of the swimmer plate on the chest while increasing the coverage of the wearer's back with the use of a SAPI plate. The effectiveness of each cut, or a combination thereof is highly dependent on the build and body type of the wearer. What works for some may not be ideal for others. However in most cases the Swimmer SAPI combo is the ideal configuration and as such it is our top recommendation for most users.

See the links below for our Swimmer / SAPI Combo Plate Options

NIJ 06 Certified Level IV Swimmer SAPI Plate Combo (26605) – Hoplite Armor Store

Search: 4 results found for "swimmer sapi" – Hoplite Armor Store

Extremity Protection

Hoplite Armor has designed and developed the world’s first viable rifle rated extremity protection system which includes Hard Armor Shoulder Plates, Femoral Plates, Side Plates, Dangler Plates and Groin Plates. 

The Shoulder Plates extend the coverage area of standard armor systems by providing lateral protection to vital organs such as heart and lungs. Shoulder plates are critical in close quarters or urban combat scenarios where rounds can come from different angles and trajectories. Shoulder Plates are far easier to wear long term as compared to side plates and provide protection to more vital organs.

Shoulder Plates – Hoplite Armor Store

Side Plates extend lateral coverage to the mid section and come in 6”x6” and 6”x8” with 6”x6” being the ideal fit for all but the largest of users. We do not recommend 6”x8” side plates for anyone under 6’4” tall as they can be extremely cumbersome if not fitted correctly.

Side Plates – Hoplite Armor Store

Dangler Plates fit inside standard 5”x8”/ Dangler Pouches provide extended frontal protection to the lower abdomen.

NEW Level III+ Dangler Pouch Plate – Hoplite Armor Store

Femoral and Groin plates provide frontal coverage to vital arteries and appendages. Modern combat techniques focus fire on the hip region in order to circumvent torso armor, making lower body protection a critical component of modern close quarters / urban combat. 

III+ Femoral Plates – Hoplite Armor Store  


Personal preference is the single most important determining factor when choosing the right size armor for any individual. The wearer must feel comfortable in whatever system and size they choose in order to maximize the effectiveness of any armor system. That having been said, the prior standard for all plates was 10”x12”. Military specifications now include a full range of sizes from Small to Extra Large, however size Medium, 9.5”x12.5” is considered the ideal fit for the 95th percentile, meaning that Medium is designed to fit 95% of all military personnel. 

In order to provide a more easily discernible size chart we focus on the height of an individual as the most important factor in determining proper fitment. See the outline below for a general height / plate size reference. Keep in mind, personal build, and personal preference are the most important factors.

If you purchase a set of plates that you feel is the wrong fit, call us for guidance and to get a quick and easy exchange.

SAPI Sizing Specifications

Size Dimensions Weight Height
Small 8.5”x11.5” 6.5 lbs <5’5”-5’8”
Medium 9.5”x12.50” 7.5 lbs 5‘8” - 6’
Large 10.25”x13.25” 8.5 lbs 6’1” - 6’4”
XL 11”x14” 9.75 lbs >6’4”


Swimmer Sizing Specifications

Size Dimensions Weight Height
Small 8”x10” 4.8 lbs <5’5”-5’8”
Medium 10”x12” 6.5 lbs



Plate Carriers

For the purpose of this discussion I will divide plate carriers into 3 categories; Concealable, Standard and Load Bearing. This does not include details regarding extremity protection carrier systems and will focus entirely on typical “torso” plate carriers.

Simply put, concealable plate carriers are designed to be easily concealed under thin clothing such as windbreakers or jackets. Concealable plate carriers tend to be simplistic in design and construction as well as lighter, thinner and less cumbersome than standard or load bearing plate carriers.

The only downside to a carrier such as this is that they do not handle the additional weight of ammunition or other equipment as well as load bearing plate carriers and can have a negative impact on performance if used to carry additional weight for long periods of time.

We currently offer the Rogue 3.0 Concealable Plate Carrier for $299

Rogue 3.0 Plate Carrier – Hoplite Armor Store

What I refer to as standard plate carriers are typically a bit more robust in design and construction, have built in padding, wide shoulder straps and thicker sewn segments. Standard plate carriers will typically utilize MOLLE webbing and component mountable cummerbunds. This allows for better weight distribution of both plates and additional equipment, but standard plate carriers are not easily concealable under clothing.

We currently offer the Mark II Plate Carrier for $395. It is, in our opinion, the ideal solution for most civilian applications. Capable, durable, lightweight and affordable.

Hoplite Armor Mark II Carrier – Hoplite Armor Store

Load bearing plate carriers, such as the Crye Precision AVS, are designed to maximize load bearing capacity while minimizing the impact on mobility. Systems of this type are expensive and tend to be a bit more scalable than is required for civilian applications. Hoplite Armor is currently in the process of developing a unique, load bearing plate carrier system that simplifies and streamlines the carrier to be an ideal solution for almost every application at a significantly reduced price as compared to similar systems.

As with all things armor related, consider the use and application, as well as the threat and your intended response to various scenarios when selecting defense related equipment.

If you have any questions, please don't hesitate to call. Our team is highly educated on these matters and will be happy to assist you.