Battery contacts for a laser level gadget used by the Joinery department. Initially they came looking for batteries. Upon seeing the inside of the battery compartment, I said it needed a good clean out first, as it looked like the previous batteries had leaked all over the place.

Cleaned it up, which was different from the usual state-of-affairs after batteries have leaked; fitted new batteries; tested. No sign of life. Time to dismember and look inside. Then I discover the level of damage underneath the contacts, as above, and that the PCB and other parts have been affected. It also appears more like water damage. Went back to check with the Joiners. "Oh, one of them was left out in the heavy rain for ages." It was BER - beyond economic repair, mainly because it's intended for indoor use. It is robustly built, as regards being dropped or knocked, but there's no waterproofing. Over £100 for a replacement, if they buy another the same.