bought most likely for one time use. I wish it was sold in smaller tubes. This is only to ensure that the spare thermistor pair is held still. The PSU is still running, so there's no reason to think it hasn't done its job. Probably something cheaper (or more readily available) could be made for this one occasion, but I didn't want to risk the client's very expensive equipment. I expect the rest to be hardened next time I need it :(