521011-1 is an Ultra-Fast fully insulated FASTON receptacle terminal designed for secure wire termination in electrical applications. This one-piece fully insulated premier line receptacle is engineered for 18-14 AWG wire with a .250 series mating tab configuration, featuring a .051 inch mating tab thickness and tin-plated brass construction. The terminal incorporates a translucent nylon housing (UL 94 V-0 rated) that allows visual inspection of the crimp and wire termination, along with a funnel wire entry and wire stop to ensure correct lead-in and full mating with various tab styles. The housing is color-coded blue for 16-14 AWG wire size identification, and the terminal is rated for continuous operation at +105°C. This receptacle is ideal for automotive, appliance, and industrial electrical assemblies where reliable quick-connect termination and shock/short hazard prevention are essential.