This Grodan Gro-Smart Tray is a durable Dutch tray with double-sided features. Use the 78-cell side to perfectly fit 1.5 in A-OK Starter Plugs or round Macroplugs. Use the mesh side for sheets of A-OK's, Mini-Blocks, or Gro-Blocks. The tray fits in a standard 10 x 20 flat and keeps the Grodan elevated from the bottom of the flat. Easily sanitize as any hard-plastic product; even dish-washer safe! This terra-cotta colored tray was designed and is exclusively manufactured by the Grodan company.