Check the listing for details. Crosman 760 - Seal Kit - Brass Ring Cup - Variant 1 & 2 - Self Cocking - L3. Condition: New. Listed at 18.00 USD. The traditional felts were loose on the aluminum spindle and tended to bulge when the brass ring and pump cup was pressed back on. I have serviced a number of 760s where the felt has been stretched down and over the aluminum rings on the piston head.