For Sale ~ 2 1/4" Armstrong / Billings Single Open-End Engineers Wrench / Heavy Duty, $100 Cash Only. Caterpillar OEM Compatible Wrench, Excellent Condition, Great tool addition to any Heavy Equipment Repair Shop / Mobile Mechanic Service Truck, Ready for use, Thanks for looking, As well as being a "usable mechanic's wrench" it also has the Vintage Rare Armstrong / Billings Wrench Markings for a collectable wrench! Contact me about the story behind it and if you have any questions (904)536.seven.four.seven.one