Donny FL Moderators for the Seneca/Sam Yang Light Hunter
Sam Yang has two different types of muzzle threads, M16x1.5 and 5/8×18. The best way to determine which threads you have is to go to a hardware store and pickup one of the size nuts. If the nut does not screw on then it must be the other size.
M16x1.5 Muzzle Threads
5/8″x18 Muzzle Threads