During use of heavy photographic instruments like DSLR or cooled cameras (often with filter wheels ), it's crucial to avoid flexures when we insert them into the telescope's focuser. This also important for visual use using large mirror diagonals and wide field eyepieces (which are often very heavy).
That's why we designed the OnAxisLock eyepiece holder that replaces the classic screw with a locking ring system. This allows you to perfectly lock the inserted accessory by rotating the outer ring (red): a special double ring tightens internal accessories with an uniform pressure. The OnAxisLock eyepiece holder also allows you to keep perfectly aligned the accessories inserted in the focuser: so you will be sure that your camera's sensor will be perfectly centered with the optical axis of the telescope.
The particular locking mechanism also prevents to ruin inserted accessory because the pressure is distributed uniformly in the barrel. With the classic screw closure the mechanical stress is instead brought on a small area and this can easily ruin the barrel.
The special design of the outer ring has been developed to allow you to lock the accessory with ease, even when wearing gloves. This way you can be sure to safely lock your camera or your eyepiece even in bad weather conditions.