Not exactly, the Sinclair you put up a link to is different. They don't show in the picture but in the description they allude to a delrin body
The Sinclair Seating Depth Tool will work with most bolt action, single shot and AR type rifles. The tool includes a Delrin action guide for most bolt-action rifles (Remingtons, Savages, Winchesters, and Rugers), a stainless steel measuring shaft, two stainless steel stop collars and complete illustrated instructions.
which looks like this
you insert it through the rear of the receiver. Better be good at math. The little plastic knurl nuts wouldn't tighten enough to stay in place (notice the crude attempt at making a slot in the top for a screwdriver
), it fit very few of my rifles and was a total PITA. And $33.00!