4 valve, Yamaha Euphonium YEP-321 & YEP-621 Valve Repair Kit (after 1986). 4 each guides, springs, valve stem felts & pads, top cap felts & pads, stem washers (metal).
See my item # 16196 for a YEP-201/201M and 16029 for a YEP-202M and YBH-301M Marching Baritone and Euphonium Repair Kit. They are different kits.
See my item ID# 16895 for a current model Water Key Spring, Screw, & Cork Set.
Contact me with your model if you wish to verify your model's fit.
