For Grass & Artificial Turf surfaces 4030 White Steel Field Event Markers White write-on surface Speeds up marking and measuring of all throwing events Also used to mark athletes check points for Long Jump, Triple Jump & Pole Vault with grass beside the runway. 4031 Yellow Steel Field Event Markers Yellow write-on surface Heavy steel plate on bottom. Used on All Weather runways to mark athletes check points for Long Jump, Triple Jump, Pole Vault & more
