... ,,etc for different rubber, likes viton , NBR, CR, etc x-ring, o-ring, square ring,,,etc for new sizes or new models ... your required.hydraulic sealing items.backups , dowty seals, u seals,o rings, wipers, oil seals, piston seals, v packings, rod seals ... the different type in different sizes.good quantity , better price. X-rings, o ring kit, square rings