Rootrainer seed starters have grooved cells that promote downward root growth and discourage spiraling, yielding deep-rooted seedlings that transplant easily and adapt quickly to the garden. Cells are 1-1⁄2" square at the top, and they hinge so you can monitor root growth and remove plants without disturbing roots. Made from plastic; may be reused. The Deep Rootrainer has 32 cells with a holding frame; and cover. Plastic 11-1/2" L x 9" W x 3-1/2" H overall with 32 cells that are 1-1/2" square x 5" H Holds 9.5 dry quarts of seedstarting mix Includes holding frame Holding tray and dome included Reusable