Use the Micro Channel Mounting Blocks for minimal secure mounting of the kayak Sailor Rig onto hard to fit decks. They can be used to fill the space under the Main Body Tube, raise the rig over hatches and hardware, and allow movement of the rig fore and aft to better accommodate different size individuals. Micro Blocks are expertly machined from a single piece of black .5 in. Delrin plastic and are designed to be cut down to the exact height needed for your application and-or shaped to it deck contours. Kit Includes: 2 Micro Blocks, 2 no. 6/32 x 2.5 in. Stainless Screws, 2 no. 6/32 x 1.5 in. Stainless Screws, 2 Stainless Locknuts, 2 Stainless Washers.