Still no operators available on their chat, so forget that. I measured the base of a 1/2" drive hard-wired bit socket with similar proportions and it's 38mm, so the 41 should be sufficient. I have both 1/4 & 5/16" bits and would like to be able to use any handle up to 1/2" with them (don't care for the retaining spring adapters). They also have impact adapters in this drive for those bits, so I guess it isn't just me looking to adapt the two.