Thermostat-180 Degrees Manufactured with OEM quality materials and safety standards by an OE Supplier. Stands up to even the most demanding automotive cooling systems. Manufactured with OEM specifications and processes. Copper case and wax compound assures rapid response to temperature changes in the coolant. Offset design, air relief valve, and OEM style seals included where applicable. Bypass Diameter: 1.16 in Bypass Length: 0.55 in Prop 65: WARNING: Cancer and Reproductive Harm - www.p65WARNINGs.ca.gov Flange Thickness: 0.07 IN Gasket Or Seal Included: No Installation Tool Included: No Jiggle Pin Weep Hole: Yes Sealing Flange Outside Diameter: 2.13 IN Start to Open Temperature: 180 Deg. F