A permanent dot mark visually penetrates into the bottleUnderground creator Arnel Renegado has created an effect he calls INFECTIOUS. The effect is simple you draw a permanent dot mark on a glass or plastic bottle and rub the bottle to create heat, mysteriously the ink penetrates inside the bottle making the water changes its color, you are in for a treat to learn the secret now!HAND THE BOTTLE FOR EXAMINATIONEASY TO DO AND PERFORMANY BOTTLENO CUTSNO STICKY STUFF