a hammer spring lock for the FX DRS, It is made from stainless steel and when screwed into the back of the block it will act like a jam nut and stop the hammer adjuster from unscrewing when the rifle is in use.

To install the unit, first give the threads in the block a good clean, getting rid of the old loctite then adjust the hammer spring to get your desired power. Next simply screw the lock against the hammer spring adjuster. We highly recommend using the dedicated lock tool (sold separately) however you can install the lock using a pair of snap ring pliers or a couple 2mm pins.

The lock is 3mm thick so you will need at least 3mm between the back of the block and the end of the hammer spring adjuster.

Please note this will not fit the newer blocks with the ball detent adjustment on the hammer spring.

We have not tested this on the other FX rifles and it may or may not fit.

The lock tool and new hammer spring adjuster are available separately

Included in the package:

• 1 X FX DRS hammer spring lock
• 1 X Sub 12 Airgunners O-ring measuring guide
• 1 X Sub 12 Airgunners box sticker
• 2 X Sub 12 Airgunners rifle stickers