ATP-Auto-Ranging-Sound-Level-Meter-SL-8928-ATP-SL-8928-P-Environmental-noise-is-a-major-issue-in-most-countries-especially-in-areas-of-high-population-&-the-sources-of-noise-&-their-adverse-effects-on-our-wellbeing-are-varied-The-superbly-designed-ATP-Auto-Ranging-Sound-Level-Meter-model-number-SL-8928-may-help-you-with-some-of-these-issues-P-P-The-ATP-SL-8928-is-easy-to-use-with-features-normally-only-found-on-more-expensive-instruments-The-ATP-SL-8928-has-an-electret-condenser