PLEASE READ CAREFULLY ; 

A NEW GENERIC SLIGHTLY STRONGER THAN STANDARD STRIKER SPRING.

SOME ON HERE ARE TOO STRONG CAUSING WASTED AIR.THIS ONE IS ONLY ABOUT 25% - 30% STRONGER THAN STANDARD ONE.

THIS WILL GIVE GOOD RESULTS WITHOUT UNDUE STRESS ON THE INTERNAL EXHAUST VALVE AND LOW COCKING EFFORT.... ALSO LESS WEAR OVER STRONGER SPRINGS TO THE STRIKER SHAFT WHICH IS CRITICAL.

# Not suitable for the Xtra fac models.#

FOR STANDARD UK AIR ARMS S41O/S310/S510/S300/S400 MODELS

#Now with FREE nylon transfer port seal to replace the thin rubber one which can blow out !#

On Some later models of the 510/ Ultimate Sporter you may have to remove 1 coil.

Always thoroughly clean striker shaft and lube with light machine oil,this is a major cause of power loss if not cleaned properly.

Listing is for 0ne [ 1 ] spring and port seal