There should be no slack in the seat belt.

不应该有任何松弛的安全带。

youdao

Fit Mighty-Tite onto any seat belt, lift the ratcheted handle a few times and easily remove unwanted slack for a tight car seat fit.

它适合于任何汽车座椅安全带，将棘轮扳手提起按压几次，很容易消除座椅安全带安装过程的松弛。

youdao

Drivers are slack about seat belts and child-seats are rarer still.

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