500FT Braided and Bonded, Black and Yellow Mason Line is made of durable nylon. A braided variety wound on a 1" diameter core. #18 nylon has a tensile strength of 165lbs. Mixed coloured options are 'bonded' for extra durability. Bonding is a process that coats the string to make it more wear, UV and water resistant. The line is stiffer and easier to tie knots and the ends won't fray as much when cut. Patented reel handle allowing you to change spools easily. Reloadable, allowing you to replace rolls of twine as needed. Allows the roll of twine to spin freely. Prevents twisting and knotting. Loose end of the twine can be secured in the convenient notch.