I really don't know! Go on there website and maybe you can get more information.
Would definitely contact the company first, though theoretically you could. Not required to hang on with both hands, just helps your balance. People in our group, including the guides didn't hang on. You're strapped in pretty good and the guides control the operation of everything.
Like Michele said your best bet would be to contact the Company. They do have documents you have to sign b4 Ziplining.
Lily I would contact the company specifically, but honestly you need to be able to hold the specific harnesses with both hands. I would wait until you have good use of both arms.
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