This "LX850" OTA (attached pix) was posted for sale on Cloudy Nights today. It does not match anything I have seen before. I own both a 10" and a 12" LX850 OTA and they do not match this unit's design. The radius blocks appear to be the original LX800 radius blocks; not the newer, more robust radius blocks of the LX850 product. But the big head scratcher is the MIRROR LOCK! This appears to be the same mirror lock used on the LX200-ACF OTAs but the focuser appears to be the current LX850 dual speed focuser. Seller says he bought it from OPT last spring.
Any body know what this is?