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The short tube should be used on CMU block and shows MPH graduations up to 60 MPH. The tall tube should be used on all other substrates and shows ml which convert to MPH up to 98.1 MPH.
The short tube should be used on CMU block and shows MPH graduations up to 60 MPH. The tall tube should be used on all other substrates and shows ml which convert to MPH up to 98.1 MPH.