A T2 thread, also written T-2, has a diameter of 42mm and a thread pitch of 0.75mm. It is also sometimes written as M42x0.75.
The low pitch distinguishes it from other M42 threads.

noctutec
Electronic collimator OCAL V3.0 MAX
( 3 / 5 )
$ 384.00
ready for shipping in 24
h

noctutec
Electronic collimator OCAL V4.0
$ 327.00
Product can be shipped as of 10.06.2025