Schaller Sure Claw

The product is, generally speaking - great. A must have, in my opinion, for any FR guitars that sports regular spring claw.
I think some Ibanez guitars used to have (or still have) some system that allows for easy spring tension adjustment (adjustment wheel or something). Sure claw is 3rd party attempt to do just that. It's such an incredible help when setting up FR equipped guitars but there's always BUT :D
So, the trouble with this product is that it's position 0 (let's call it a position when your current springs catch the regular claw is so much more forward that, most likely, you'd need to cut into guitat. In my case (Jackson Dinky) I had to remove pretty much all the wood there was under the backplate, towards the neck, like the whole 1cm. Fortunately, I measured it beforehand and there was no need to go further but have that in mind. Check Schaller webpage for technical drawing and measurements before buying this product. That's why it's a 4 not 5 star review.

Otherwise a great product and will install it on all my FR guitars, for sure.

Also - beware if you use more than 3 springs. No space for that and, I guess, you'd need to change springs for harder ones in this scenario.