Mc Master-Carr has an assortment of Chuck keys. If you click on product detail it will show a pdf detailing the pin size. It would be a big help if you knew the brand name of the chuck.

They also sell multiple size Chuck keys that are similar to a 4 way lug wrench.

John

~ J Lucas
2006 GMC Envoy 4.2 I6
2023 Ram 2500/Cumins 6.7 I6
2010 Jeep Grand Cherokee (Wife’s)
2002 Silverado 2500 Gas 6.0
1941 Chevy 1/2-Ton
1942 Chevy 1.5-Ton SWB
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