The Yellow Braided Mason's Line has a special braiding process which aids the elasticity and eliminates sagging. The tight braid can be pulled taut along block and line holders for a straight accurate line. This tube of 500' of solid yellow line is easy to see on the job site. The nylon line won't mildew or see the effects of moisture and humidity like other lines. The line is tested to 170 lbs. for superior hold. The line is abrasion and alkali resistant and stands up to the abuse of a job site from trowels striking it. Proudly made in the USA.