Additional Drilling Equipment - New Thrust washer that will fit the Following tongs. HK500C (requires 4) HK3700 (requires 4) TR350 (requires 4) Oil Country 4500 and all Copies (requires 2) (thin washer should be placed on top of Idler Gear) Made in the USA. Will only accept lower offers if purchasing more than 1. Location: Lubbock, Texas. For complete listing information please select the Click To Bid button to see this item on eBay.