Low Tension Version is around 10g of tension, ideal for embroidery machines. Fit Elna Models: eXpressive 820, eXpressive 830, eXpressive 830L, eXpressive 850, eXpressive 860, eXpressive 900, eXpressive 920, eXpressive 940 Fit Janome Models: MC15000V3, MC400E, MC500E, MC550E, MC9850, MC9850SE, MC9900, Skyline S9