1917-1927 Chevy car and 1918-1928 Chevy Truck radiator caps

Chevrolet cars produced from  from 1917-1927 and Chevy trucks from 1918-1928 had a 2-1/4" OD cap with a vertical knurl and 16TPI internal thread. Also fits: Chevrolet 490 Late Model Chevrolet 1917-1927 Maxwell 1915-1918 Oldsmobile Light Six Star 1924 They were originally offered in a bakelite finish but many of our customer have requested chrome over brass so we offer that finish with or without a hole for the motometer. Bakelite is a phenol-formaldehyde resin, formed from a condensation reaction of phenol with formaldehyde. The phenol and formaldehyde are derived from coal tar and wood alcohol e.g. methanol.  High costs, complexity of production and a brittle nature caused bakelite to fall out of fashion but we still love the look.  We achieved a similar finish with an aluminum alloy and a protective ceramic finish that replicates the looks of the original synthetic resin.