If you want a sleek, stylish looking side mount, you will want to look at the M-2! This mount is specifically designed for use on vertical surfaces. It has an attractive black molded body that looks great on any vehicle. When installed, the coax connectors are concealed on the inside of the vehicle.This mount may be used with single or dual installations. We recommended that it be used with Firestik or Firestik II antennas up to 3" (92cm) or FireFly and RoadPal antennas up to 4" (1.2m). Accepts 3/8"-24 tpi threaded antennas and accessories. This mount comes complete with all of the required mounting hardware, rubber gasket, metal reinforment plate, nylon insulator and ground terminal lug. If purchasing a coaxial cable, consider our Model K-8 for single antenna installations or Model K-9 for dual antenna installations. If using a spring with a base diameter larger than 0.700", a split lock washer is required between the mount and the spring to ensure proper seating of the spring to the mount surface.DIMENSIONSMounting Surface Area: 3.125" (79mm) x 1.675" (43mm)Upper Mounting Hole Diameter: 13/32" (10mm)Lower Mounting Hole Diameter: 13/64" (5mm)Mounting Holes, Center to Center: 1.50" (38mm)Outward Protrusion From Mounting Surface: 1.88" (48mm)Maximum Mounting Surface Thickness: 0.28" (7mm)