The 202A121-4/86-0 from TE Connectivity / Raychem Brand is black color heat shrink boot with shell size 21. This heat shrink boot has 0.969" (24.61mm) to 0.390" (9.91mm) large diameter and 0.969" (24.61mm) to 0.209" (5.31mm) small diameter. This is adhesive coating, flame retardant heat shrink boot with length of 1.500" (38.10mm). Operating temperature range is from -55 to 135 °C ( -67 to 275 °F ).