Chalkballs have proved to be useful in training, especially for police. They break apart on impact, marking the target with white chalk powder. Thanks to their high quality, you can practice precision shooting and be well prepared for using other kinds of ammunition. We offer chalkballs in calibers .43, .50 and .68 for each of your Umarex Defense Training Markers. Perfect for all markers with magazine feeding system, because the slicker and more stable outer shell optimizes the feeding out of the magazine into the chamber, thus minimizing the risk of bursts while feeding or in the barrel.