Features: Easy, fast & accurate positioning. Precise microfine adjustment with dovetail and mounting hole. One knob allows for simultaneous tightening / releasing of all 3 joints. Uses a maintenance-free, mechanical central tightening system. Quick, stepless lock. Pre-tensioning: With this model you can lock the bottom portion of the arm in place even if the dial is turned. It's great for taking multiple measurements on the same machine, and for protecting the gauge when the dial is twisted to release the arm. High-quality, red anodized, light alloy. Swiss made. ROHS and REACH compliant. Overall Height(mm): 335 Radius of Movement(mm): 280 Microfine Adjustment hole diameter: 3/8" Dial Gauge and base are NOT included. Still need an Indicator? Check out our selection here. Dimensions (mm) [see 2nd picture]: L=280 L1=170 D1=16 L2=110 D2=10 Threads [see 2nd picture]: M1=M8 (not fully shown in main picture) M2=M6 The Fisso Strato M-28 F 3/8" Articulated Indicator Gauge Holder Arm is a fantastic choice for easy & accurate measurements in a snap. Add your favorite dial gauge, and attach the arm to your machine or base. Then all you need to do is put it into position, twist the knob, & you're ready to start measuring! Still have questions? You can contact us, or take a look at the Fisso Resource Center.