One 8" BK7 blank for sale or trade. The disk is 1.5" thick. I intended to use it to make an 8" Mak corrector but it has been on the shelf ever since. I just bought a 10" LX200GPS and I hope raise some funds for SCT accessories or a low-power wide-field 2" eyepiece. If you have a trade in mind, plus or minus cash, let me know. Price is $75 plus shipping.