For cilantro, radish, dill, and spinach. 24 round holes, 13/64" (5mm) in diameter. Possible spacings (depending on seeder sprocket combination) from 1/2-2 1/2" apart. Seed rollers have slots or holes to cup seeds, allowing accurate singulation of very small to medium size raw seeds or pelleted seeds, and are compatible with even some larger seeds. Made of a special anti-abrasion plastic to prevent buildup of static electricity.