Easy Test to Determine Your Model:
If positions 2 & 4 are quiet while positions 1, 3, and 5 buzz on your 5-way Pickup selector switch,
the Dual Layer BzzzzKill is right for you. This is the case for the vast majority of Fender Stratocasters® manufactured in recent years, which come standard with a reverse-wound middle pickup.
If you hear buzz in ALL positions on your 5-way pickup selector switch,
the Single Layer BzzzzKill is right for you.