Invert mini twist on/off asa

[Aidz2704]

Does anybody know how much these sell for, or how to get it off the invert mini. It is an american import which was £45 and works a treat, but unfortunately seems stuck in the asa but i think it is designed to do this for safety reasons, but i kind of need the mini on it's own now

 

[BDN]

The NDZ threadsaver has two flats to screw on/off. Does need a large spanner, though (from memory, cos I'm on holiday at the moment), 25mm or thereabouts. Or an adjustable spanner or mole wrench. Think the SP ASA also has two flats to do the same.