DuPont Tyvek 400 Hooded Coveralls with Booties and Elastic Wrists are composed of flash spun high density polyethylene which creates a unique, nonwoven material available only from DuPont. Tyvek® 400 provides an ideal balance of protection, durability and comfort of any limited use fabric technology. Tyvek® 400 fabric offers an inherent barrier against particles (down to 1.0 micron in size). Protection is built into the fabric itself; there are no films or laminates to abrade or wear away. Tyvek® 400 fabric's durability advantage over microporous film fabrics delivers consistently better barrier, even after wear and abrasion. Pin locking slider locks in place when the pins on the puller are pushed into the zipper elements.