what will music become in our rapidly changing cities? it appears to be scratched into the cork on the front. snorkel the reef or explore surrounding caves. that means its perfectly safe for use with 3v or 5v power and logic. its a great idea, but a little too challenging. for someone who knows very little about the process, i felt at ease with you by our side. easy to clean - the bottom of the mat is made of waterproof and dirt-resistant material, thanks to which the mat can be used both indoors and outdoors. 