This is the only real clunker of the bunch - it’s been made and sold for over 45 years. LOOK at the stone-holders - they have to be assembled and ALIGNED on a dead-level surface. After some time, the guide-rods will loosen and start to flop around. Go to their website, and look at “Parts & Accessories”. They offer two different clamps for extras - their standard and “soft-grip” - both have four slots for 17, 20, 25, and 30 degrees. Here’s an opportunity to build your own customized kit. The two extra matching holes in the centers of their jaws are for use with their pedestal stands, and they offer THREE - a one-piece plastic - a two-piece aluminum - and a third that uses a modified aluminum C-clamp and pedestal-post.