1x Circular Root Control Disc designed for growers using 1Pot XL module or system, the Root Control Disc prevents roots from encroaching on the AQUAvalve. We recommend the Disc is used gold face up though growers may still use the sheet effectively gold face down if they wish. There is no wrong way to put them in the pot as either side up works. Also, you can get a couple grow cycles out of the root control material. If the copper coating oxidizes off, you can still reuse them as there is copper woven throughout the material as well.