Riser blocks are used when mounting telescopes to rails when more room is needed between the rail and the telescope. This is particularly important with our smaller telescopes (SVX70T, SVX80T) when a camera is mounted to the rear and it cannot be balanced on the mount. Using Stellarvue risers with a longer rail allows adjustable travel to attain balancing over the focuser. The rail does not hit the focuser or camera since the riser block lifts the telescope 2.5" above the rail.
This set includes two riser blocks (RS-SET) and our TP13 Losmandy sized rail that is 13" long. (Note: If your system requires a Vixen rail instead of this Losmandy rail, use the RSS-V instead).