T2 thread attachment replace camera lens by using a T2 adapter
The "T" is said to stand for Tamron, a Japanese manufacturer, who in 1957 made a line of aftermarket camera lenses all using their T2 T-mount as a universal fit to 35mm SLR cameras of various manufacturers.The original T Mount slides onto a T mount lens. It is secured only by 3 set screws that match a channel on the lens mount so that the lens barrel is not deformed by the set screws, and it can therefore be removed with no problem.