On the new model Browning A5 there is a huge flare (jug) just ahead of the choke tube and despite all the pissing and moaning you hear about the final constrictions of the Invector DS tubes, mine pattern and perform the way they should. My 12 gauge DS Mod tube has a final constriction of .010, and the IM tube is .015, but they pattern as true mod and IM.