Chest harness - a harness used in conjunction with a seat harness to keep the body upright in case of a free fall (into a crevasse, for instance).

胸式安全带，用于连接座式安全带，以保证坠落时身体直立。也用于在携带重物下降时支撑身体。

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Lock Tite chest clip helps position harness straps for optimal performance. It's super-strong and curved for a comfortable fit.

胸扣使肩带能调节到最佳的位置，它超级坚固并弯曲成舒适的形状。

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The large rack of gear dug into my shoulders and my jury-rigged chest harness made it hard to breathe.

WSJ: Training for the Big Wall | By Michael J. Ybarra

To enhance creative expression during shooting PENTAX offers an optional lens adapter with wide-angle coverage to 20mm, and the SportMount Chest Harness which allows for the hands free capture of adventures and features a quick and easy mechanism to review your images and footage without having to remove the camera from its mount.

ENGADGET: Pentax expands ruggedized series with Optio WG-3, Target-exclusive WG-10

It's a video camera worn in a harness on the chest and indeed he was seen, a witness said so, with this device.

BBC: Toulouse school killer 'had camera around his neck'