Morton Safety Break System for Stained Glass Work The running tool is the most versatile part of the Safety Break. The push block and button are always used together; this combination is more powerful than the runner and works best with transparent glass. The Safety Break has three components The Running Tool was developed for use with the Portable Glass Shop and is the best breaking tool available to eliminate or lessen burs and flares Center the glass score over the red button, position the push block oer the galss and button, and push down