This device is usually used for forearm training but can also be used to assess the physical parameters of your body and your age. The kit contains 2 devices, for two arms.

We don't sell this device ourselves. You can buy it, for example, from
https://www.amazon.com/dp/B08393YNLF or
https://www.amazon.fr/dp/B08394M4NN

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en français:
Le grip mètre vous aide à déterminer la condition physique de votre corps.

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по-русски:
Измеритель хвата помогает определить физическое состояние вашего тела.

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en español:
El medidor de agarre le ayuda a determinar la condición física de su cuerpo.

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all'italiana:
Il misuratore di presa ti aiuta a determinare le condizioni fisiche del tuo corpo.