Do it White Braided Nylon Chalk Line, 500 ft. is crafted from nylon in a durable braided chalkline construction that ensures long-lasting performance. This chalk line is resistant to rot and abrasion, making it highly durable even when exposed to cement or alkaline materials. The line is shrink film wrapped and features the Do it label for ity. With tubes measuring 1/16 inch in diameter and an impressive breaking strength of approximately 70 pounds, this product is designed for reliability and strength. Its white color and braided nylon construction make it a versatile tool for various marking and layout tasks. Model Number: 307091