3" dove tail system (530mm)

Baader 3" rail (76 mm base width of prism)

These standard width rails were first developed by the Losmandy company for 'Losmandy' GEM mounts. Later, the standard was adopted by Celestron, then by AstroPhysics, Software Bisque (Paramount), and several other manufacturers. Today, almost every manufacturer has a clamp for 3" rails in their product range. Only the tracks themselves, as a standardized part, are very difficult to source - here is the solution.