Sturdy, durable, not easy to fade, long service life. Replacement accessories, easy to install and easy to use, can perfectly replace old or bad Upper Knife 412585 (Spare Part Numbers: 93-414125-85/000, 416321701, 416669301.) and Lower Knife 550449 (Spare Part Numbers: 93-415504-49/000, 416325901.) For MODELS: T-3, T-33, T-34, T-34D Fits models: 4762, 4772, HOBBYLOCK 2.0, 756 Fits models: 300, 430, SW432, 4350D, 5030, 5949L.