[gbeal]

If you have Pentax M42 fittings or lenses, and wish to use filters in the optical train, this is for you. This is handy if you are using the older, affordable Pentax screw lenses for wide-field imaging, and decide a bit of Ha could be fun.
Solid as, has M42 Pentax screw thread, (so M42x1) female on one side, and the same thread male on the other. Total depth of the drawer is 21mm, quite thin by filter wheel standards.
Drawer then uses "slides" into which you screw the filter of your choice. This unit is supplied with a 2" filter slide, but other sizes are available, for example 1.25" and T sizes.
AU$100 plus actual post. I'll look after the PayPal fee.
PM's please.
Gary