What features would be most valuable in a water bottle designed for construction crane operators who work at heights all day?

Construction crane operators work at extreme heights where access to water is limited. Which feature would be most valuable in a specialized water bottle for these professionals?

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Insulated design that keeps water cold for 24+ hours
One-handed operation with leak-proof locking mechanism
Attachment system that secures to crane cabin structures
Large capacity (48+ oz) to reduce refill frequency