(4) ArtUSA Panels provide excellent sound absorption, especially in environments requiring high frequency noise control. Made with ArtUSA exclusive willtec® foam, ArtUSA Acousti™ Mini Panels are a safety-minded choice for use in machine enclosures and other confined spaces. Willtec foam is Class 1 fire-rated according to ASTM E 84 for flame spread and smoke density. It can withstand constant temperatures above 300° Fahrenheit, and will char but not ignite at temperatures above 1100° Fahrenheit. Willtec natural meets the corner burn test UL1715.