Rion Hobby 2, Grand 2, and Prestige 2 greenhouses include one roof vent, but if you’d like to add another (and who wouldn’t?), you’ll definitely want to check out the Rion Roof Vent for Hobby/Grand/Prestige. With a heavy-duty aluminum frame, this vent features a polycarbonate panel that’s built to withstand even the harshest weather. Prop it open to improve air circulation, close it to build heat on cooler days.