LESOLEIL 225pcs Rubber Hydraulic Tool O-Ring Metric Assortment Kit SAE Pneumatic Air Common Sizes - Our kit includes 18 of the most used O-ring sizes Durable Nitrile Rubber - Nitrile rings resist heat, most petroleum and silicone fluids, hydraulic and non-aromatic fuels, and solvents Standard Sizes - Most commonly used Standard SAE sizes Organized Storage Case - The storage case keeps the o-rings arranged by size 225 Piece Rubber O-Ring Gasket Assortment Kit