Carter Evolution 20 3 Finger Resistance Release Aid. 

Excellent condition, only been shot a few times, comes with original packaging, Instruction sheet and Allen Keys to adjust.  Has been shot less that 100 times

Unlike the previous versions, there is no need to replace to spring to increase the release tension.  One screw (and a locking screw) are all that's needed to set it between 8 and 40lbs of holding weight.

Price includes shipping to uk mainland.  Based in West Sussex.