Jiffy Pellet Prefilled Handling Sheets. Simply place in a tray, add water and plant. Convenient, easy, quick setup! These popular sheets each contain your favorite Jiffy Pellets, ready to expand for seed germination or rooting cuttings. The lightweight plastic sheets hold the pellets in a grid formation while in use. Since the Jiffy pellets are locked into the sheet, they stay put when water is added. Each insert measures 10" wide x 20" long. Each 1/2" thick compressed Jiffy peat pellet expands to a 1-1/2" diameter (36 mm) x 1-5/8" tall cylinder. 72 pellets per sheet.