i picked up these starr socket adapters a while back on ebay. they used to be available at napa but they were discontinued. i think the sell bought all of the leftover stock.
a very simple design. three adapters in the set, 1/4-3/8, 3/8-1/2 and 1/2-3/4. they have a magnet to hold the socket and ratchet to it and the two larger sizes have a hole for the detent ball. way more compact than the more common adapters. and have the bonus of adding a spinner . stackable for multiple drive size jumps as well.
