I’m not talking about a hex key that extends in length but one where it can collapse in on itself to increase in size.
I did some digging online but all I could find was a patent from a company called TeleHex but it kind of sounds like they came and went in the mid 2000s. They’re website doesn’t seem to exist.
I feel like it could save space in my pocket compared to a typical hex key set or a multibit.
I was hoping I could at least find a bootleg version on Ali Express.
This is a solved issue. Use a bit set to have the different heads you need to fit on one driver. You can get ones that store the bits inside the driver.
Any telescopic mechanism is going to have a hollow centre and be weaker and prone to deforming. Larger hex keys are used to deliver more torque, making them hollows defeats the purpose of having a larger key, and small bolt and hex key should have been used to save weight and cost (or the same size to standardised the tooling).
Do you think the hollow core would make that much of a difference? The head of the key would still be solid and the depth required for each different size likely wouldn’t account to much. There would probably maybe half an inch at the opposite end from the head. If someone used a t like design, with the top bit being where the grip and hollow portion are, I imagine that would likely cut down a bit on torque exposed directly to the hollow section.