The push down clamps come in 2 lengths-2 ½” and 4”. The kit has 2 short and 2 long with the nut driver but the 2 ½” and 4” can be purchased separately. These are typically used on the 1600, 2500, and VR48 t-slot tables. They are used for holding down spoil board and other items to the machine table (i.e. parts, machinist vises, etc.).
There is a notch cut into each end- one is shallow, the other is deeper. Between the notches and the long bolts for the t-nuts, they are very versatile for holding objects in place.
Hope that helps, check back next month for another Quick Tip and check the archives for more helpful information.