SCT Corrector - Adapter for 55mm Backfocus

35.3mm T-to-T spacer (M42 female to M42 male).  This adapter takes up 35.3mm of the Starizona SCT Corrector's 90.3mm back focus. Leaving 55mm of backfocus to work with. Ideal for common setups such as DSLRs with T-rings, or ZWO cooled cameras and their 16.5mm and 21mm stock adapters. 

Note: If you're purchasing the Starizona SCT Corrector IV 0.63x Reducer/ Coma Corrector, this adapter is included with your purchase.