8MR151 are former 8MR150 series rotation stages with newly integrated opto limit switch for home position reference
8MR151-30 - models made with hole through in the center of platform, 30 mm in diameter.
8MR151-1 - models made with socket for 1" optics in the center of the platform.
8MR151E - models made for imperial standards (thread and hole spacing).
8MR151...-MEn1 - models have feedback encoder mounted on them, more information here.
For vertical mounting angle brackets 2VP150, 2AB151-002 are available. Chek 2AB151-001 as an example of the angle bracket for XY motorized rotation stage assembly.