PVA AI prefit barrel question

Sogan

Sergeant
Full Member
Minuteman
Jun 11, 2013
1,499
556
Going to order an AI prefit from PVA. The prefits ask whether it is a small shank (27mm x 2.0) or Large (30mm x 2.0). My gun is an AI AE MKIII and I’m waiting to get a 6creedmoor barrel for it. I’m assuming I need the small shank barrel?