The Drop-In Hidden Horn V.3 kit includes a horn plus one chrome and one white decorative billet screw-in grill. Hole size 2-3/4” diameter. At 111 decibels and a frequency (Hz) of 370±20A, this horn meets US Coast Guard's COLREGS and ABYC standard A-23 for use on vessels under 12m (39'). Constructed of powder coated steel and injection molded nylon
