Resun Blue 4 LED Emergency Strobe Light Head Waterproof Surface Mount Deck Dash Grille LensLED light Color : Blue 4 LED , ( 1PCS ) 16 selectable flash patterns - capable of alternate and synchronized flashing. Compatible with all automobiles and devices equipped with a 12 Volt DC power source ! Waterproof Surface Mount with Snap-On black bezel included. Last pattern recall / memorized function . Weather-Proof IP67 ! Size :Length:4 21/64" (11cm) Width: 1 3/16" (3cm) Height: 1 17/64" (3.2cm) Polycarbonate lens and housing and completely resin sealed electronics. Self-contained, external flasher not needed, easy operation !