The Triplett SoniChek PRO (3550) is a professional sound level meter designed for industrial applications where IEC651 (Type 2) and ANSI S1. 4 (Type 2) standards are used. This highly accurate (plus/minus 1.5 dB) meter features A/C weighting， fast/slow response time， analog bar graph， max hold， AC/DC analog output and a tripod mount. The SoniChek PRO is well suited for a variety of commercial and residential applications such as fire alarm， home theater， plant maintenance， HVAC installations and more. Includes windscreen， AC/DC analog output cables， USB cable (for power only)， 4 AA batteries and case. Founded in 1904， U. S. -based Triplett Test Equipment continues to be on the leading edge of specialized testers. Whether supplying vital test equipment to the U. S. Signal Corps during WWII， or providing the railroad industry with essential testers to ensure the safety of their crews and the public， Triplett prides itself on developing innovative， reliable and durable test equipment that also won't break the bank. Triplett's catalog contains a wide array of test equipment parts and accessories such as multi-meters， voltmeters， cable testers， security cameras and security camera accessories， wire cable mapping kits， video monitors and other specialty testers. They serve industries such as HVAC， security， electronics and electrical， telecom and more.

Designed according to IEC651 (type 2) and ANSI S1.4 (type 2) standards with an accuracy: plus/minus 1.5 dB (94 dB at 1kHz)

A/C weighted measurement with fast/slow response reads 30 dB to 130 dB and has a frequency range of 31.5 Hz to 8 kHz

AC/DC analog output

Analog bargraph， maximum hold and tripod mount

Microphone windscreen