I saw that disclaimer about it not being a measuring tool. I wonder though, if the seller didn't put that after getting some negative feedback from an idiot who bought the product thinking it was an equivalent to the park tool thing. If the bushing is a tight enough fit on the bolt, you could probably just use calipers to measure between the rod of this tool and the wheel rim, instead of the park tool sliding post thingy.
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Owner & co-founder, Cycles René Hubris. Unfortunately attaching questionable braze-ons to perfectly good frames since about 2015. With style.