Genuine GE Appliances product constructed with highly flexible heavy-duty four-ply aluminum foil laminate for durability and easy installation Dryer duct kit is designed to fit most gas and electric dryers and can easily be cut to a custom length Effectively vents hot air and moisture to keep your dryer operating at peak performance Duct measurements: 4" diameter x 8' in length UL® approved and designed to withstand temperatures up to 258(degree)F