The Extreme Max Clean Rig Spacer allows for a clean and professional-looking installation of your 1-in or 1.5-in Ram Ball Mounts or any other marine electronics with a 2.5-in mounting base, including depth finders, GPS and more. Each Clean Rig Spacer is pre-drilled to fit standard mounting patterns. Due to the wide variety of surfaces and equipment the spacer may be used with, mounting hardware is not included (Extreme Max recommends #10 stainless steel hardware). Includes ten Clean Rig Spacers. For larger mounting bases, see Extreme Max 3002.4567 Clean Rig Spacer for mounting bases up to 3-11/16-in diameter. Extreme Max Clean Rig Spacer- Small, 2.5-in Diameter- 10 Pack | 3002.4564