These greenhouse seals adapt to all situations. Besides the parallel clamp including the full length of the jaws, I often used in situations where other traditional clamp seals are of no help. For example, if you assemble two boards you want perpendicular, a traditional pump attached greenhouse will allow you to operate the clamping tongue / rebate, but not to maintain the 90 ° angle for the moving part not based on anything. Therewith, positioning it to straddle the two plates and is tightened (or was discarded) and check the angle with an angle bracket. The only complaint that justifies the star less: the diameter of the handles (wooden) is very small and the paint on the wood is slippery. Shame to have skimped the above, otherwise it would be perfect.