So, in the process of strain-measuring, when we apply the normal lever extension meter, it is confined by conditions, such as the install pattern, measurement standard and so on.

因此，进行应变测量时，应用常规的杠杆引伸仪，受到安装方式和测量标距等条件的限制，往往只能测量轴向一定范围内的平均应变。

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Series 100xl furnished with test lever and extension thermostat for installation in the hot water outlet line or directly in the tank tapping.

系列100 XL配置测试杆和加长温控杆，适用于安装在热水出水管路上，或直接安装在容器的螺纹孔上。

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The lens retraction and extension is faster using the Zoom Framing Assist button than the zoom lever, and allows the photographer to keep the camera more stable for the shot, this is particularly helpful for those trying to zoom in and shoot pictures of animals or moving subjects.

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