The Palram Hybrid Series 6' x 4' Greenhouse is an ingenious balance of two advanced polycarbonate panels for the optimum environment. The crystal clear side panels offer over 90% transmission for growth, while the 4mm twinwall roof blocks up to 99.9% of harmful UV rays to prevent plant burn. The integrated rain gutters and down spout disperse rain water to the ends, making it ideal for water conscious gardeners to collect.