The Junior Clamp has a mouth opening of 1.75 and can attach to both flat and round tubes. It has two threaded mounting points (1x "-20 & 1x 3/8"-16) that allows you to attach a variety of accessories such as an F&V Articulating Arm. The Junior Clamp tightens via a metal kip lever. The Junior Clamp has a reinforced rubber lining on the mouth that allows for a no-slip grip. This clip is strong yet small in size and is easily stored in the pocket of your kit bag or clothing.