Macroplugs have a slit that allows easy insertion of a cutting. Thses loose round plugs fit perfectly in to the Gro-Block hole. For best results with Macroplugs always insert them in a tray with individual cells. The individual cell will make sure the plug stays closed around the stem of your cutting. Same great product with new packaging. Now 50 Macro Plugs in gold foil bag that can be hung up.