B3301: Ultramid B3301 is an intermediate viscosity. PA6 grade. It conforms to FDA requirements including(中间粘度，尼龙6级。它符合美国FDA的规定)
B33L: Ultramid® B33L is a lubricated polyamide 6 grade of intermediate viscosity that is well suited for the production of biaxial oriented and cast film and monofilaments.( 尼龙6是一种中间润滑粘度等级，十分为双轴导向和流延膜和单丝生产的理想选择)