[Allan]

I had these fitted to my dob, but changed them out for a higher CFM variety. They work great at cooling the primary mirror to ambient temperature when mounted on the mirror cell.

These are high end, German made and exhibited no vibration when in use. They are also very quiet.

Fans have wires that don't terminate, so a socket or switch setup will need to be attached to the ends to suit your own use.

$25 each posted in Australia.