Exceptionally high clamping forces can be obtained with this hold down. The arm is free to pivot independently, all levered forces are exerted downward, without any loss due to horizontal slippage from the canting action of the hold down post. The fine grooves on the post resist upward forces, yet still allow easy entry into a 19mm diameter hole. The 250mm hold down post gives you 200mm of clamping capacity, matching the 200mm throat capacity. Used vertically on the top of a bench, or horizontally in a side skirt.