Features: Easy, fast & accurate positioning. One knob allows for simultaneous tightening / releasing of all 3 joints. Uses a maintenance-free, mechanical central tightening system. Quick, stepless lock. High-quality, red anodized, light alloy. Swiss made. ROHS and REACH compliant. Indicator holder and base is not included. This listing is for 1 arm. Still need an Indicator? Check out our selection here. Dimensions (mm) [see 2nd picture]: L=200 L1=120 D1=10 L2=80 D2=9 Threads [see 2nd picture]: M1=M8 M2=M6 The Fisso Strato S-20 Articulated Indicator Gauge Holder Arm is a great choice for quick, simple and accurate measurements. After you attach it to a machine or base and add the adjustment / gauge holder operation is simple. All you need to do is position it, turn the knob & you're good to go. Still have questions? You can contact us, or take a look at the Fisso Resource Center.