Orion 5251 Large Binocular Tripod L-Adapter Essential accessory for coupling large astronomical binoculars to a field tripod for visual use Viewing through heavy astronomy binoculars can be difficult and tiresome - this adapter lets you attach your binoculars to a tripod so you, and your arms, can enjoy long viewing sessions in comfort Holding high-magnification binoculars in your hands can cause your views to be shaky - coupling a high-power binocular to a tripod provides a stable and steady platform to view from Captive 1/4"-20 bolt threads into tripod adapter receptacle feature found in the bridge of most binoculars