Amazon.co.jp: Durable,O Ring Seal Gasket 4mm Thickness Black NBR O Ring Seal 31/32/33/34/35/48/50mm OD Oil Resistance O Ring Seal Washer (Color : 50pcs,Size : 31x23x4mm) (Color : 50pcs, Size : 40x32x4mm) :
EAI Nitrile Rubber O-Rings 15mm OD 10mm ID 2.5mm Width, Metric Buna-N Sealing Gasket, Pack of 25: Amazon.com: Industrial & Scientific
Amazon.co.jp: uxcell O-Ring O-Gasket Rubber NBRO Rings 2.2 x 2.5 x 0.1 inches (56.8 x 63 x 3.1 mm), Pack of 20 : DIY, Tools & Garden
Amazon.co.jp: Durable,20pcs 1.9mm Thickness O Ring Seal NBR 5/6/7/8/9/18/19/20mm OD Nitrile Rubber O Rings Sealing Gaskets 70 SHORE O Type Ring (Size : 15x11.2x1.9mm) (Size : 15x11.2x1.9mm) : 産業・研究開発用品