This device has been engineered to clamp the EMCO/CHASE bilog and bicons with tubular baluns. The clamping hole is approx 23mm diameter and the hole centre line is 4.5cm above boom surface. It sits onto the EMCO 5.2cm square mast boom which has a series of 3/4" holes allowing a delrin screw (item 855)to grip the mount. The under surface has a single 7/8unf threaded hole. The clamp is 15cm long, 8.5cm deep & 6.3cm wide. Weight 1.1Kgm.