The Otto Bock aluminium "gold / silver" look-tuned hook (model 10A18 [link]) showed some malfunction in our warm (hot?) summer weather with no air condition.
Hot (here achieved by running water over it, but a sunny 30 deg C weather will do) will expand the metal so that the Otto Bock Standard Aluminium Hook will not close any more - unless you give it a little whack
The blocked Otto Bock hook can be brought back to function by cooling it.
Obviously, the designers worked in air conditioned laboratories and saw no need to take their puppy for a spin for HOT WEATHER GARDENING WORK.
Well guess what I had done.
The implications are staggering.
Just imagine running around with lots of coolant steam running of your blech hook.... whoo whee.