Stephanie is correct,,,,, they are great mounts and well worth the money....
I went a different route with my Panther though,,,,, I used an Accushot 1 piece mount and shimmed the rear of the scope with 2 pieces of 35 mm film negative. (did the same thing on my RWS 350 magnum). Worked great and mount hasn't moved one bit on either rifle. The Accushot is much cheaper, like $16 bucks, and they work well.
I'm not bad mouthing the BKL though,,, it's a great mount for sure..... Just thought I'd mention another (cheaper) option.
Jeff