Couplings can be used to mount Vixen prismatic binoculars on a variety of smooth surfaces. Another use is to balance your existing tube (SC, MC). With extra weight, it is fixed to the prism rail of the tube, making it adjustable for balancing eyepiece-side accessories.
The coupling has a total of four 1/4" photo tripod nut threads: one in the center and three more on the edges.
