Vintage Brown & Sharpe Mfg. Co. pocket gap gauge No. 644. Brown & Sharpe Mfg Co. is one of the oldest and probably most significant machine tool and precision tool builders. Founded in 1833 by David Brown and in 1853 Lucian Sharpe became a partner and the name became Brown & Sharpe. This gauge measures approximately 3 1/2" when closed. Gauge is in "as found" condition. Nice vintage tool.