Rope Polyp Twist 3/8x50 Specially formulated twisted polypropylene rope that is much stronger, has half the weight, and costs less per foot than manila rope. Resistant to rot and abrasion and is not damaged by petroleum products, mildew, marine growth or many chemicals. Lightweight, strong rope used extensively in many ways. Waterproof, floats, and sliceable. Must be bound or fused on end to prevent raveling.