3PCS Microphone Preamplifier Audio Amplifier Preamplifier Electret Microphone This device is a transistor preamplifier with an electret microphone, connected at the input. Application:  - for sound for video surveillance DVR,  - for security system,  - for audio signal for LED indicator VU meter, - for audio signal for power amplifier,  - for megaphone,  - and others. Electret microphone included. Output level: 0.750 V.  Power supply DC - 3 to 12V. Overall dimensions PCB 25x22mm (0.98"x0.87"). Package Content: - 100% Brand New in original packing. - English and Bulgarian Instruction Manual. - 1x 3PCS Microphone Preamplifier Audio Amplifier Preamplifier Electret Microphone. Shipping: - All items will be checked before packing. All items are new and of high quality. - We will ship within 1-3 business days upon receipt of payment, excluding weekends and public holidays. - We only send by registered mail or courier, with tracking number. - Delivery time is from 5 to 30 business days depending on the destination. Customer Services: - Please contact us, we will assist you in any way possible and aim to answer all emails within 24 to 48 hours.