About the Meade #918A Diagonal Prism - 1.25"... The Meade #918A Diagonal Prism diverts light 90 degrees to the telescope's main tube, permitting a more comfortable viewing position. This high-quality diagonal features a prism made of the finest optical glass and is fully coated for maximum image brightness and clarity. Standard equipment with a wide variety of Meade Telescope refractors, Schmidt-Cassegrain 8 and 10" models, LX200, LX200GPS, LX200ACF, all LX90 models, and older Meade SCT's. Meade #918A Diagonal Prism - 1.25" Features... Diverts light 90 degrees to the telescope'''s main tube Permits a more comfortable viewing position Made of the finest optical glass Fully coated for maximum image brightness and clarity Meade #918A Diagonal Prism - 1.25" Specifications... Equipment Type: Star Diagonal Size: 1.25" Angle: 90 degrees Type: Prism Coatings: Fully coated Application: All 1.25" Focusers - Refractor, SCT, Mak Meade Product Number: 07202