Auxiliary Speaker When you need to boost the sound of your detector--the smallest, yet loudest speaker on the market. While this speaker is not weatherproof, the uses are nearly limitless. Mounts easily within vehicle. Must be wired directly to 12-volt power source. Dimensions: 2.25"W x 2.25"H x 2.25"D. Useful for models: 9500ix, 9500i, 8500 x50, 8500, SRX, SR7, Solo S2, RedLine.