The Kestrel ATC Ring Adapter offers a rotating collar with integrated arca swiss mount for your Swarovski ATC Spotting scope. Made with an advanced industrial additive manufacturing process from extremely durable polymers, this adaptor is woven throughout with continuous carbon fiber for extra strength and durability. This is primarily made for the ATC, but would be a very stable mount for your STC as well!
I agree completely with L.N. the concept is good, but man is it touchy. I can't decide if it is stable enough, when locked down, so still comparing to using a plate on the bottom of it vs the adaptor. The product is entirely too expensive for what it does, to me, given how touchy it is. You can certainly rotate the scope and having an Arca foot is nice, but I think it makes the scope a bit less stable on the tripod head.
Great idea but could have been executed better. It's touchy in that the ring wants to slide back ever so slightly and when re-tightened it locks up your spotter adjustment ring. It's definitely a two hand operation when rotating your scope. Is it worth having on the scope? Most definitely but for the price I expected a more refined product.
Using on my STC works great.