Ultra-fast sewing machine Jack JK-9270-performs 12 stitches of the chain type. This series is equipped with a U-shaped platform, which is very convenient to handle products of cylindrical shape, such as sleeves, Trouser legs. The main element here is the implementation of a seam in the lock on light density materials. All seams are smooth, neat and identical, even when sewing at maximum speed of four thousand revolutions per minute. The oil in the minimum required amount is served even in the most remote places. At the U-shaped surface of the fabric is straight, not gray and not konchaetsja due to the differential promotion of tissue: the lower and puller.   Advantages: Economically 71%. High speed and wide range of settings. Cantilever cylindrical structure. Convenient and simple adjustment of the distance between the needles. Adjustment button stitch length Источник: https://leg-prom.com.ua/en/shvejnoe_oborudovanie/p-obrazna_platforma/jack_1970d