This tube of 500' of the yellow line is great as mason's line for a strong, tight line, or any odd jobs where a superior line is needed. The special braiding process creates extra elasticity which helps eliminate any sagging in this line making it perfect for laying out even rows of block and brick. This long-wearing, tough, #18 solid yellow line is easy to see on the job site. The nylon line won't mildew, nor be affected by oil or mortar. The nylon material won't absorb water or see the effects of moisture and humidity like other lines. The tight braid can be pulled taut along block and line holders for a straight accurate line. The line is abrasion and alkali resistant and stands up to the abuse of a job site from trowels striking it. The line is tested to 170 lbs. for superior hold. Proudly made in the USA.