Lehigh NST181 Nylon Twine - Mason Line Constructed from continuous filament nylon specially treated to knot securely. It is much more durable than natural fiber twines because of its superior resistance to abrasion, rot, mildew and most chemicals. Available in neon colors for high visibility.Lehigh NST181 Nylon Twine - Mason Line Features:; Twisted Nylon #18 x 800 ft. White; Core Wound