Features:

• "White noise" sound machine masks unwanted noise for use in the home and office
• Recommended for restless sleepers, shift workers, infants, children, students, apartment dwellers, office workers and many others
• Single speed
• UL-Listed in USA and Canada
• Made in USA

Editor Reviews:

Product Description:
Marpac Sound Screen & SleepMate 580 combines American ingenuity and craftsmanship to create a lightweight, yet durable appliance capable of many years of reliable service. Marpac sound conditioners create a consistent, smooth sound of rushing air. The tone and volume of the sound are controlled by simply rotating the "cap" and "collar" of the housing. This "white noise" sound effectively masks unwanted noises and creates a sense of calm, making it easier to concentrate, relax and/or sleep. These sound conditioners are recommended for restless sleepers, shift workers, infants, children, students, apartment dwellers, office workers (for confidentiality) and many others. The single speed 580 is made of durable plastic housing suitable for travel or use in the home or office.

Rating : - Marpac 580 Sound Conditioner
I think this product works exactly as it says it does. it's a nice alternative to running a fan in the middle of winter, and it is small enough to travel with. i definitely recommend this product to anyone who needs a white noise to sleep.