The Hercules LR Arca Adapter is specifically designed to work with the Hercules LR Spigot for that tripod.

The adapter will fit onto the Ascent / Sentinel 12mm spigots, but with the Hercules, it is designed to index onto a machined tongue along the top of the spigot.

The photos below show this design more clearly.

The purpose of this is to lock the position of the adapter to the locked position of the spigot. This was required for use with some larger military rifles, which weighed over 15kgs and needed the positive locking that this design could offer.

The alternative for a conventional Arca-Swiss fitting would be the Classic Arca Adapter, which would work as an interface between the Arca-Swiss rail on the rifle or optics and the 12mm spigot of the Ascent tripod.

If you need any additional information, please don't hesitate to come back to us.