These Sentry bags are made of non-woven point bonded 2.25 oz Polyester material with excellent filtration qualities. Built stronger then the Sentry II bags, these bags can withstand maximum temperature of up to 400°F. Each sample bag comes with a 2 x 3" sewn-in tag for sample identification and a drawcord for closure. Please note the bags come packaged 100 per pkg. Shipping weight for 100 bags is 4 lbs. Quantity discounts.