The lenses liked to be cleaned once in a while, but be careful with rubbing sand and dirt on the lenses, just water and a clean cloth will do.
And for those oily sunscreen stains, it's best to add a drop of dishwashing liquid to a wet cloth.
Why aren't you providing a cleaning cloth?
Most cleaning wipes are made of microfibers, and unfortunately do not contribute to improving our climate. We assume that you probably have a microfiber cloth at home, and therefore do not need to make one especially for you. If you do not have one, we will gladly send you an unbranded one.
Keep them at room temperature.