Yellow touch points simplifies preventative maintenance and training requirements. Stone care daily maintenance capabilities is a complete floor care process that restores the natural beauty of porous stone and produces a remarkable, long-lasting shine with the 3M™ Stone Floor Protection System. ec-H2O NanoClean™ technology electrically converted water is created by an on-board e-cell that generates millions of very tiny microscopic bubbles known as nanobubbles that promote the cleaning efficacy of the solution. Quiet 67 dBA noise level.