The choice of material impacts weight, thickness, and durability. UHMWPE (Ultra-High-Molecular-Weight Polyethylene) is favored for being extremely lightweight and buoyant, making it ideal for maritime or long-duration missions. Aramid fibers (like Kevlar) offer excellent heat resistance and stability but are sensitive to moisture. For hard plates, Ceramic (Alumina or Silicon Carbide) is essential for breaking high-velocity projectiles, though it is more fragile and prone to cracking if dropped compared to steel plates.