Yep. Strip of rubber car tube works a treat. Been using it forever. Make sure lens are clean and dry. Stretch it over. To remove in a hurry grab it half way along it's length and a bit of upward pull will flick it off. Carry a spare in your pack in case you flick it off in a hurry and lose it. If you strike a night out in the bush just use the rubber to light a fire. Generally 15"- 17' is about right for most scopes.
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