The dual compact electric trumpet horn exterior is constructed of a 100% stainless steel with a 304 stainless steel diaphragm. Sealed sound unit achieves a 110 dB(A) rating at one meter. Use the holes in the bracket as a template for the location of the mounting points and wiring. When installed the trumpet should point slightly downward to permit water drainage. 12VDC, prewired. Meets ABYC standard A-23, for use on vessels under 39′.,WARNING: This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit P65Warnings.ca.gov