This mini and compact Telephone Amplifier significantly increases the volume of any telephone handset or even cellular phone. Ideal for phone conversions in noisy locations and for people with hearing trouble.Features include:Increases the volume of any telephone handsetWorks with cellular or regular phonesEasy to useEasy to carry along for travelStop straining to hear others talking to you on the phoneDimensions: 1.25 x 2.375 x 2 inchesBattery includedInclude retail packaging