This is the second time I've bought the extra power recoil spring, the first went into a PSA GF3 and this one went into a Zastava M92. Both times the item shipped quickly and got to me without issue. When you first install the spring you can expect a few instances of failure to eject but after the first mag everything runs smoothly. Paired with a decent muzzle brake this will make any AK pattern rifle or pistol a real smooth shooter. Much easier to stay on target for quick follow-up shots. 10/10 would recommend.