4" Red LED Marker/Clearance Light. STL43RB. 10 diodes. Used on Turtle Top shuttle buses, RVs, motorhomes, and trailers. Light has a 4" diameter.. Sonically sealed, waterproof. Accepts standard PL-3 Connection. PC rated: functions as Stop, Turn & Tail light grommet mounted. We sell more than shuttle bus lights. Please browse our store for all of your shuttle bus, church bus and RV parts needs.