I like the fox ones, and you can adjust them by warming them in hot water

I had a set of 10' rods made up with the handles having a 1” gap, 2” from the rear of the reel seats, so could use the Solar butt rests quite tight fitting but on the blank instead of on the cork. Also doubles up to stop the rod being dragged forward as the thicker cork section (has blanking plate to protect) acts as a stop & will not pull through the butt rest. Similar to what Shimano have done on their TX Intensity range of rods (their flagship range). Had this done with full Duplon but would also have it done with full cork on next set of rods I buy.

At the moment with my full corks, I still use the Solar P1 butt rests, but place a piece of Camo Duck tape on the section where I push the handles into the rests. Keeps the reels & tips at same distance from everything on the bars for aesthetic purposes (we all know you will get any self respecting carp picking a bait up if the rod tips & reels are all over the place!!!