- Starlight Instruments Adapter 2.5" for William Optics Megrez 80/90mm and 6/8" RCSI-A25-2003-14 $250.00Starlight Instruments Adapter 3" for William Optics FLT110 with TEC f/6.5 LensSI-A30-1903-6A $250.00Starlight Instruments Adapter 3"for Explorer Scientific and Meade 127mm with Aluminum OTASI-A30-1903-ES130 $250.00