[Picatinny To Arca Swiss Adapter / Mount]
"Vortex Optics Picatinny Rail Tripod Mount"
After comparing a handful, I opted for this one. I grabbed it on Scamazon for about $25 bucks:
https://www.amazon.com/gp/product/B000FSGHZ4/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1 My only gripe is the small hex head / screw that's used to tighten the mount to the picatinny rail,
but, I already intended on replacing it with a thumb-screw or d-ring.so no tool would be needed..
Anyways, they work Great!
Just remember - You'll want to use a solid / sturdy tripod w/ a good sized leg-span, since the setup can get top-heavy..
I use mine w/ my heavy duty metal tripod w/ heavy duty heads.
I set it up on my light weight carbon fiber tripod ONCE and Never Again.
If you'd like to get a lot of free range motion out of things, I recommend a nice "fluid head" for the head/mount.
I use those and a few different pistol-grip mounts. Also try to avoid plastic.. All metal mounts are the way to go.
Shot of a direct to tripod [no head] install for rigid-mounting - used when I take rifle photos:
Sam -