Conventional roulette is inconvenient to measure in the crevices, folds, blind grooves. I have attached the model to the usual roulette kind of spout — G-shaped bracket of sheet metal; its length is 50 mm.
Now in a remote place enter the nose and make the measurement, adding to the readings on the tapes marked 50 mm — easy and simple.
N. SMOLIN, Chelyabinsk