As low as $47.49/mo with or . (Pay in 4 interest-free payments)
ALPINESTARS A-4 Plasma Roost Guard — Black/Red/White (XL/2XL) The ALPINESTARS A-4 Plasma Roost Guard is engineered for high-protection off-road riding with an anatomically profiled fit and advanced impact-absorbing armor for roost, impacts, and all-day comfort. Key Protection & Comfort Features Semi-rigid thermoplastic polyhedron chest protector paired with a Nucleon Plasma back protector for lightweight, breathable, adaptive protection. Nucleon Plasma back protector uses viscoelastic biobased polymers, formed into a structure pliable in all directions while efficiently dissipating impact energies. Lightweight, highly ventilated design for strong impact force dispersion and absorption across riding positions. Ultra-vented chest armor with engineered shell geometry for structural strength and load performance. Flexible over-injected side wings follow body contours to improve comfort and freedom of movement. Detachable, adjustable perforated rib & shoulder padding for targeted coverage against tire roost and impacts. Perforated 3D mesh chassis adds protection and airflow while helping guard against roost. Bionic Neck Support (BNS) compatibility via BNS shoulder pull tabs. Fit, Materials & Sustainability Adjustable shoulder and side straps for an optimized performance fit. Removable soft tactile thermoformed shoulder padding for comfort. Soft tactile lining reduces skin contact while maintaining protector integrity and minimizing tearing risk. USDA certified bio-based eco-friendly sustainable impact-absorbing material. Optional Race Kit Compatibility Compatible with the Nucleon Plasma Extended Roost Coverage kit (Upper/Lower Chest Extensions + Y-Strap System) for using the A-4 chest protector without the back protector. Specifications: Off-Road / Adventure Touring / Dual-Sport / UTV / ATV • Size XL/2XL • Type: Chest • Base Colors: Black/Red/White • Weight: 2.43 lbs • Dimensions: 20.59" x 15.08" x 3.39" .
Anatomically profiled for all forms of off-road riding
Features a semi-rigid thermoplastic polyhedron design chest protector and a Nucleon Plasma back protector that are engineered to be lightweight, breathable, comfortable, adaptive, and protective
Key Features
Highly flexible Nucleon Plasma Back Protector constructed from viscoelastic material engineered from biobased polymers and formed into a structure that is pliable in all directions while maintaining the ability to dissipate impact energies
Lightweight and highly ventilated, this protector offers strong impact force dispersion and absorption while ensuring maximum coverage areas in all riding positions
Lightweight and ultra-vented chest armor
The chest outer shell’s design achieves the desired structural strength and imposed load performance when compared to flat or unfaceted surfaces
The over-injected flexible side wings of the chest protector follows the body's contours for comfort and freedom of movement
Optional Race Kit — Engineered to be compatible with the Nucleon Plasma Extended Roost Coverage kit which includes Upper and Lower Chest Extensions, and an additional Y-Strap System to use the A-4 Chest without the back protector
Features highly perforated, adjustable, and detachable rib and shoulder padding for additional rib and shoulder coverage against roost and impact
Construction
Equipped with adjustable shoulder and side straps for an optimized performance fit
Removable soft tactile thermoformed shoulder padding for enhanced rider comfort
The lining on the back protector offers a soft tactile feeling against the skin while maintaining the integral structure of the protectors and reducing the risk of any material tearing
The lining is ribbed for superior airflow while also reducing the amount of material that is in contact with the skin
The perforated 3D mesh chassis also offers additional protection against tire roost
Bionic Neck Support compatibility via the BNS shoulder pull tabs
USDA certified bio-based eco-friendly and sustainable impact absorbing material
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. (Pay in 4 interest-free payments)
