Features: The Strato U-Line is desirable when extreme precision is required (measurements in the µ range) Easy, fast & extremely precise 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. High-quality, red anodized, light alloy. Swiss made. ROHS and REACH compliant. Overall Height(mm) 259 Radius of Movement(mm) 204 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=204 L1=116 L2=88 Threads [see 2nd picture]: M1=M8 (not fully shown in main picture) M2=M6 The Fisso Strato U-Line A-20 P 3/8" Articulated Indicator Gauge Holder Arm is a top choice when highly accurate measurements are required fast and easy. Add your dial gauge to the microfine adjustment, and attach the arm to your machine or base. Then just 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.