The Really Right Stuff PRA-135 adapter plate was designed to attach multiple products to the 1.5" dovetail lever release and screw knob clamps. The PRA-135 is the male section of picatinny with a male section of the RRS dovetail adapter that mounts onto the top of tripods. FeaturesCNC machined aluminum Adds a male picatinny section to the top of the Really Right Stuff 1.5" dovetailSafety screws to prevent equipment from sliding Perfect addition to your shooting setup