Rion GH4-12HG 8'6' ' W x 24' L Hobby Greenhouse, 5 Roof Vents - Hunter Green (5) Roof Vents (1) Louvre Window (5) Auto Roof Vent Openers 8'6" W x 24' L x 6'10" H Greenhouse Frame has pre-drilled holes for attachment to Concrete Slab, Great Gift Idea.