The IRF90 to 2″ Visual Accessory Adapter allows you to attach a 2″ mirror diagonal and eyepiece to your IRF90 rotating focuser.  Used in conjunction with other PlaneWave adapters to space your eyepiece at the optimal position for your CDK model.
See the adapter diagram (under the Downloads tab) for more information on the adapters needed for your CDK.
The back plate on all of the CDK models has four mounting positions for a finder mounting plate.
The finder mounting plate attaches to the back plate of the telescope and the quick-release finder bracket attaches to the mounting plate.
If the telescope is used on a German Equatorial mount it may be convenient to purchase two finder scopes, one for the east and one for the west side of the telescope.
The finder scope is a Baader 10×60 Varios with mounting rings and L- bracket.