Whistle

The whistle should be loud and work well in the water. Attach it to the helmet side strap with an elastic cord (a hair tie works well) that is long enough to easily reach the mouth but no longer. The most memorable codes are the ones that match the word number:

• 1 blast = stop
• 2 blasts = off-rope
• 3 blasts = give-more-rope
• 4 blasts = take-up-some-rope
• 5 blasts = this-is-monstrous!-guided-rappel!

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  Fox 40 Classic
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  Kordas Silbato