521586-2 is an ultra-fast fully insulated FASTON receptacle crimp terminal designed for quick-connect applications in electrical assemblies. This one-piece terminal features a tin-plated brass construction with a 0.051 inch (0.51 mm) mating tab thickness and is rated for 22-18 AWG solid, fused, and stranded wire with an insulation diameter range of 0.060–0.110 inches (1.52–2.79 mm). The terminal meets UL-310 specification for quick connect terminals and is UL listed under File No. E-66717, with a UL 94 V-0 flammability rating. Key design features include a funnel wire entry, wire stop, visual inspection capability of the crimp and wire brush, and color-coded housing (natural color) for easy identification. The terminal operates reliably at temperatures up to +105°C and is commonly used in automotive, appliance, and industrial electrical harness assemblies where secure, insulated connections and shock hazard prevention are essential.