Valcom 5 watt talkback, self-amplified, built-in volume control Marine speaker. The V-1048M features the easy Omni-Lock I-Beam clamp mounting system. It's weather-resistant for indoor/outdoor use, it resists deteriorating effects of salt, sun, high humidity. It's equipped with O-ring seals, features stainless steel hardware, and comes in a white finish. Dimensions: 7.38" H x 10.0" W x 10.4" D (18.75 cm x 25.4 cm x 26.4 cm)
This product has a Valcom Power Unit rating of: 0
This model also comes with one-way feature, see V-1030M.
For installation information, use this Valcom PDF file: V-1048C 
