That's a tie rod end clamp.

The tie rod has a left and right hand thread. Loosening the two clamps allows the alignment guy to change the length of the tie rod to adjust toe in.

Both clamps would have to be loose to have any effect on the length of the rod.

Jim

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14 E250 BlueTEC black. 45k miles
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94 E320 Cabriolet Emerald green 152k miles
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