4-inch Test Flat, thin but efficient 1st Surface Mirror, accurate to 1/12th wave-of light, Multi-Over-Coated-Surface(Look's so brite, it looks like Silver)...Not a Scratch on This~!!
Came out of a X-ray Machine array..Rodenstalk Company, in Germany..
Shipped with USPS First Class Package.
Filed under: Eyepieces & Accessories