OK, here is more info:
New EAA / Tanfoglio 22LR made in Italy conversion kit that will fit any caliber large frame EAA Witness pistols, 9mm, 10mm, 40S&W, 45ACP and 38 super. Has threaded 1/2"x28 muzzle for sound suppressor use and comes with a knurled thread protector. Complete kit with threaded barrel, slide assembly (black), recoil spring, guide rod, cleaning brush, instructions and 10 round magazine in plastic case.