Hey guys sorry for the delay, I haven't been able to do much prototyping due to a number of orders over Black Friday week. The attachment point at the front is very similar to the High Tower Armory couplers, but it sticks out of the front about 3/8" into the U shaped void just ahead of the magazine in the magazine well. As long as your extended magwells are about 52mm in length or greater, I should be able to make an elongated neck for them to fit into the magwell fully. Since I make these to order, the neck length can be customized from person to person.