The low profile design protrudes only 2'' from the stock taillight baseplate45 dual intensity red LEDs behind a spherical lens design to produce a bright red running and brake lightPre-'99 models must use a Pre-'99 Taillight Baseplate Kit part #s 2010-1418 or 2010-1419 (sold separately) to install on earlier models.'22-'24 Low Rider ST (FXLRST) and '22 Low Rider El Diablo (FXRST) require wiring adapter part # 2130-0352 (sold separately) for installation.'20-'22 Tri Glide Ultra CVO (FLHTCUTGSE) requires 2 wiring adapters, part # 2050-0417 (sold separately) for installation.