I said it upthread, and I'll say it again. It appears as if the Stag ambi charging handled are the unbranded Radian Raptor charging handles. Considering that a Raptor goes for around $80 each, getting the Stag version for $15 each is a smoking deal.
They are not Radian Raptors. Radian themselves confirmed that they used to make them for Stag but no longer do as of about 4 months ago, and that these are knockoffs.