This is on my W210. I loosened one of the straps by wedging a screwdriver into the trapezoid-shaped crimp and wiggling it left and right; that gave enough slack to lift the perforated part off the tang. Now that I'm reinstalling, it looks like you need some sort of special crimper to tighten it?

I have it pretty tight, and the tang is angled in a way that you would have to tighten the whole strap before it'll clear the tang. But I'm still nervous that it'll make its way loose on its own. Any special tips or tricks for tightening this? Why don't they just use something that resembles a radiator clamp?

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280