Momentary only Z41?

Anybody have a momentary only Z41 LOTC? I just traded for one and it only works by pressing the button, you can't twist it to make it stay on. I believe it is an old switch but its in mint condition, it says "Sure-Fire Laser products fountain valley, CA" I kinda like it this way now that used it a little.

The Z41 is the standard body LockOut TailCap as used by the 6P / M3 etc.
(Z41-BK black for 6P/Z2 etc, Z41-HA Hard Anodised for M2/M3T etc)

In normal operation the TailCap can be rotated clockwise onto the body such that the light activates constantly (constant-on).

There is a zone within which the light is off unless the push button pressure switch is pressed (this is momentary-on/off).

When the TailCap is rotated anticlockwise there comes a point past which the light does not activate when the push button pressure switch is pressed (it is locked out)

If you are using the Z41 on a standard SureFire (such as a 6P/M3 etc with SF123A batteries) and screwing the TailCap fully onto the body does not activate the light constant-on then something is wrong.
To help find out what it would be useful to know exactly what flashlight and components/batteries/lamp assemblies it is being used with.

Al