This is waltons 12 x 8 extra tall polycarbonate greenhouse has a very spacious interior and is fortified by a sturdy aluminium frame which is powder coated in evergreen colour to make it more appealing and extremely durable for daily usage these greenhouses double sliding doors and glazing are supported by the aluminium frame to offer you better quality and more practicalitywe have used polycarbonate because it doesnt shatter in extreme temperatures like glass these greenhouses come uv t