Sterling Seal and Supply (STCC) OREPD278 O-Ring, Number-278 Standard is Good for Steam (400 Degree F), Hot Water, Sunlight, Silicone Oils and Greases, EPDM/EPR/EP, 12" ID, 12-1/4" OD: Amazon.com: Industrial & Scientific
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Value Collection - O-Ring: 2-3/4″ ID x 3″ OD, 1/8″ Thick, Dash 232, Viton - 02050888 - MSC Industrial Supply