“one bottle (of) water”

2018-07-17 17:11:11

I've seen a photo of a sign, from a site that I believe is a hiking route in the US, warning about extreme heat. It reads

WARNING!

Extreme heat

Minimum 1 bottle

water per person

No sandals

Wear hat

Is using "one bottle water" instead of "one bottle of water" a common abbreviation in contexts like road signs?

Is "bottle" being used as an unit of measurement? I'm thinking of an usage such as "1 kg apples" (without "of") that is – I believe – the standard writing for "one kilogram of apples" (with "of") in contexts such as recipes.