What do I use for lenses? Neoprene (wetsuit material).
Down here we have neoprene in the form of stubbie coolers (beer can cooler) and they are the right shape and pretty cheap.
I use them on nikkor ais glass as well. I have a few "coolers" and even a spare -hey that must mean I need another lens! I even got an autographed one from Dirty Pierre himself! (offense language warning)
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