The QHY-OAG-M Off-Axis Guider is for medium-size cameras having sensors such as APS-C, APS-H or 36mm x24mm sensor (e.g., the QHY(IC)16200A), and other matching accessories like the QHYCFW2-M filter wheel. The body and pick-off prism size is the same as for all QHY Off-Axis Guiders. It is just the telescope/camera interface which is sized to accept thread adapters of different diameters. Whatever the diameter of the interface, there are six 3 mm holes and the same thickness of 10 mm (without adapters installed.) Both the telescope side and camera side adapters have a thickness of 3 mm. The final thickness of the OAG depends on whether you need to use just the telescope side thread adapter or both adapters. If you are using the QHYCFW2-M, for instance, it will connect directly to the OAG-M, and you won't need to use the camera side adapter.
The QHY-OAG-M has an interface diameter of 62 mm and will accept both M42/0.75 and M54/0.75 adapters. The OAG-M comes with both sets of adapters (two M42 and two M54), giving you more mounting flexibility. You can use either size adapter on the telescope or camera side. The QHY-OAG-M supports camera models with APS-C, APS-H, and 36x34 sensors, including the QHY16200A, or as mentioned earlier, you can attach the CFW2-M directly to the medium off-axis guider.
All QHY-OAG models have an 8mm x 8mm multi-coated pick-off prism. Its position can be adjusted as desired and then locked into position with a thumbscrew. It also comes with a locking, multi-thread 1.25-inch focuser having a focusing range of about 6 mm (1/4"). If you use the QHY5L-II--or others having a similar form factor--as your guide camera, its position is adjustable when inserted into the QHY-OAG. These two adjustments will give you a wide range of focus accommodation.