Etymotic’s ER-200 Personal Noise Dosimeter is an affordable, easy-to-use screening device which provides a great guess of sound sip as well as alerts a user to a risk of over exposure. The ER-200 facilities dual modes of operation such as Normal Mode as well as Quick Check. The normal mode measures as well as arrangement your sound sip invariably for up to sixteen hours, whilst a Quick Check mode measures a surrounding sound for dual minutes. If we have been interested, we can buy a Etymotic ER-200 for $99. Each squeeze comes with 3 AAAA Alkaline batteries. [Etymotic]