Brown & Sharpe TESA 0560013 Depth Measuring Foot with Locking Screw for 6"/150mm Caliper, 75mm x 6mm Measuring Face Depth measuring foot for use with Brown & Sharpe or Etalon surface calipers (sold separately) with a measuring span of up to 6" (150mm) 6mm x 75mm measuring face, ground for flatness Locking screw holds gauge securely Hardened stainless steel for durability and accurate measurements