I've been trying out a Gitzo 1371 head recently. For some reason it has a second locking knob for the forward/backward tilt. I've circled them here in the photo, one is also a handle but both are required of them will lock down the head. As far as I can tell they both do the same job. It's kind of annoying having to deal with both of them to adjust the head.

Anyone know why they did this? I feel like I should just tighten one and ignore the other but I feel like they must have used two of them for a reason.

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