Piston Ring Tapered Compressor Fitting Sleeve – Full Set This tool can be used with any piston from any manufacturer to easily compress the piston rings smoothly and evenly. Anodised for a friction free, long lasting finish. Each sleeve is tapered with a larger initial starting size down to the specific bore size required and greatly reduce the difficulty installing high performance piston rings. This full set includes the following – 1 x 86mm Sleeve 1 x 86.5mm Sleeve 1 x 87mm Sleeve 1 x 87.5mm Sleeve