My vintage MAC M6T has a center detent. It also has a thinner and longer bar compared to most others. It's 5-3/4" long. For comparison purposes, my two 1/4" vintage Craftsman USA t-handles both have a 4-1/2" long bar.
I use 1/4" sliding t-handles enough to keep the ones I have around, but not enough to probably miss them much if they weren't there. I think it's one of those tools where the more 1/4" drive tools you own, the less useful a 1/4" sliding t-handle will be for you. They can perform a lot of tasks, but most can be done better with a different tool.
I use mine occasionally to turn small taps with my Lisle tap socket set. The 4 smallest tap holders in the Lisle set are 1/4" drive. In some situations, that setup works better than a regular tap handle. I also occasionally put a socket on my t-handle and use it as a "backer wrench" when tightening small bolt/nut combinations in low clearance areas where a wrench won't fit as a "backer".
My most common use for a 1/4" sliding t-handle, is I put it into the top of my Proto J4769 1/4" drive socket handle and use it to break fasteners loose before removing it and spinning the fasteners out the rest of the way by hand with the Proto handle. A fast and simple way to perform quick small jobs.
Proto Industrial Tools - Safety Obsessed
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