Marpac, Sound Machine Marpac Size: 5-3/4 X 3-1/4 Inches, Count of 1Product Description Dohm, Marpacs signature sound conditioner creates the smooth, soothing sound of rushing air, also known as white noise, to effectively block noises across a broad range of frequencies Dual speed version (formerly known as the Sleepmate Soundscreen 980A)has two speeds that allow for greater flexibility in achieving perfect tone and volume settings The white noise produced by the Dohm can also be used as a shield to provide