Baader T2 Maxbright star diagonal mirror with 1/10 lambda surface quality - Flexible star diagonal mirror with best transmission for a perfect image on the telescope. Sitall glass ceramic - no expansion coefficient. 140 coating layers for 99% reflection - scratch-resistant and durable for life. T2 internal thread on telescope side - T2 external thread on eyepiece side 99% mirror coating with dielectric coating according to Zeiss factory standard. Particularly robust housing with T2 connection on both sides and excellent optical quality. More free aperture (35 mm) than with 1.25" and thus a larger image - can even be used with 2" eyepieces.