Materials based on theSpectra fiber are also used in various vehicular protection applications. Spectra Shield PCR designed from the Spectra fibers offers a floatable protection module, which almost does not absorb moisture – an important consideration for amphibious vehicle and floatable protection. The Spectra high strength polyethylene based fibers were introduced in the 1980s. It is 10 times stronger than steel, these are 40%, stronger than aramid fibers. The Spectra Shield is constructed from parallel strands of fibers held in place with a resin, every new layer is cross plied at right angles and the entire structure is fused into a composite structure under heat and pressure. The 3rd generation Spectra Shield uses an integrated Ceradyne ceramic face plate, defeating high velocity AP rifle rounds. This type of protection is widely used in the Small Arms Protective Insert (SAPI) used with modern body armor.