The rings are divided into two types: M-type and F-type.When the M-type ring is attached to the filter drawer, the thread on this side is configured as a male thread. Usually this type of thread is used to connect to the camera or camera side devices.

When the F-type ring is attached to the filter drawer, the thread on this side is configured as a female thread. Usually this type of thread is used to connect to the telescope or telescope side devices.

There are totally 6 rings which can be used to produce M42/M48/M54 male or female threads for the filter drawer. Users can combine these rings to meet the needs of their own applications. It can even be configured as male threads or female threads on both sides as required.

M-42/M-48/M-54 Male Thread Rings

F-42/F-48/F-54 Female Thread Rings

Except for F-54, the other 5 rings can be attached to the drawer frame through threads, without using tools such as screws or wrenches. F-54 is not threaded. If one side of the drawer frame needs to be configured as M54 female thread, just put F-54 into the drawer frame.