Features Replacement Base: The base is used for depth measurement dimension with depth dial indicator, with precise and stable structure. Smoothly Surface: The base surface is hardened and ground, provides smoothly operation, ensuring accurate measurement. Securely Clamping: The base uses threaded knob, the clamping is tightened and stable, not easy to fall off, reliable for usage. Stainless Steel Material: Made of premium stainless steel, the base is resistant to corrosion, rust and temperature, has long last durability. 3 Extension Rods: The base comes with 3 extension rods of different specifications, which are 0‑10mm, 10‑20mm, 20‑30mm. Specification: Item Type: Depth Dial Indicator Base Material: Stainless steel Clamping Hole Diameter: Approx.8mm/0.3in Extension Rod Specifications: Approx.0-10mm/0-0.4in, 10-20mm/0.4-0.8in , 20-30mm/0.8-1.2inPackage List:1 x Depth Dial Indicator Base 3 x Extension Rod1 x Storage BoxNote:Match the appropriate size model before use. Package List 1 x Depth Dial Indicator Base 3 x Extension Rod 1 x Storage Box