The device is based on the technology of air pressure sensor. Push in lower portion of carabiner to attach it to strap, rucksack or clothing. 𝐑𝐄𝐋𝐀𝐓𝐈𝐕𝐄 𝐀𝐋𝐓𝐈𝐓𝐔𝐃𝐄 𝐌𝐎𝐍𝐈𝐓𝐎𝐑𝐈𝐍𝐆 – The digital hiking compass is equipped to monitor the relative altitude during your adventure.
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