This 4.24" tall die-cast metal bracket connects both roof prism and porro prism binoculars to a camera tripod for extended no-shake viewing. The sturdy adapter body is narrow enough to fit between the barrels of even large aperture roof prism binoculars which otherwise might hit the body of a conventional wider tripod adapter. It will support the weight of even large 80mm binoculars.
The top of the light-weight (3.2 oz.) bracket has a knob with a tethered bolt that threads into the 1/4"-20 thread hole that's hidden beneath the decorative cap in the center hinge of many roof and porro prism binoculars (unscrew the cap to be sure that the center post of your binocular has the threaded hole before ordering this product). The base has a 1/4"-20 thread hole that fits the 1/4"-20 thread attachment bolt on the top of every photo tripod's pan head. The bracket is curved in a subtle S-shape to help put the center of gravity of the binoculars closer to the center of the tripod mounting plate. This reduces the chance of out-of-balance binoculars tilting unexpectedly.
When used for astronomical binocular observing, some people complain that this type of tripod adapter can give them a literal pain in the neck from crouching under the binocular with their head tilted back to look at the skies. We have found that a more comfortable way to use this adapter for astronomical observing is to lean back in a lawn chair or chaise lounge, let two of the tripod legs straddle your own, and tilt the tripod back to you, so that the far leg of the tripod leaves the ground. The tripod proper becomes a bipod. The hand that you use to hold the tripod effectively becomes the third leg of the tripod. This lets you lean forward and back to scan the skies, with a minimum amount of pain-inducing neck contortions.
Also, to keep from being stabbed by the pan handle of the tripod, put the binoculars on the tripod backwards, so that the pan handle points away from you, under the objective lenses of the binocular. You can still reach the handle to control the side-to-side and up-and-down motion of the tripod pan head, but it can no longer poke you in the chest or throat.
