45-Degree mirror adaptors are the key component needed for creating a custom periscope.  With a couple of mirror mounts, a long post and two sliding clamps, you can use these 45-degree adaptors to create a 1/2-, 1-, or 2-in. diameter custom periscope to your exact height specifications.

The New Focus 9920, 9922, and 9924 45-degree mirror adaptors have a thru-hole aperture allowing the optical beam to be both transmitted and reflected; perfect for beam splitting applications.

The UPA-45D 45-degree adaptors are not only made to be installed into mirror mounts but have a threaded base to allow fixed post mounting.  In this capacity, they can be used to direct an optical beam from a horizontal trajectory to a vertical one.