BA29095: Regular Rate Meter Cartridge (black)The black medium rate meter roller is for rates from 9. 07 up to 59 kg ha (20 up to 130 lb acre) for seeds such as wheat, barley, canola, and small soybeans up to 6. 35 mm (0. 25 in.) in diameter. This is also used for medium rates of fertilizer. This is the most commonly used meter roller. There are 10 flutes on this roller, which are 18. 5 mm (0. 73 in.) wide at the top of the flute, 12 mm (0. 47 in.) at the bottom of the flute, and 8 mm (0. 31 in.)