With an enhanced aluminum coating giving 96% reflectivity, this diagonal has much to offer. Attach this diagonal to your telescope via a 2" threaded barrel that accepts 49mm filters. This diagonal allows use of the flip mirror to change between its standard 90 degree 1.25" eyepiece or the multi purpose eyepiece/photography port straight through, yielding 100% transmission. This port not only fits many photo adapters but also unthreads to a standard 42mm T-Ring thread
