The Herdim aluminium crack clamps are not only extremely low weight, they also show twisting clamping jaws which are flexible and perfectly accommodate to the contours of the instrument. The risk of chipping the edges when repairing a table or bottom crack is minimized. The non-slip jaws hold the clamp securely even when applied close to the upper or lower end of the instrument body. They also adapt to the inner bouts and the tight radii of the corners. Materials: Arms and bearings high-strength aluminium alloy (weight 45-50 g). Jaws silicone type elastomer, not colouring, glue-rejecting. Thumbscrew brass.