AudioControl ACM-1.300 ACM Series compact mono subwoofer amplifier * 300 watts RMS x 1 at 2 ohms - Breakers Stereo and Performance
Infinity Primus 3000A 300W RMS Power Compact Mono Subwoofer Car Amplifier System Bundle with 12" 1200W Max Power High-Performance Car Audio Subwoofer and Amplifier Wiring Kit - Road Entertainment
0.1 Black 4D Furnishers HSWA-300 Mono Amplifier for Subwoofer 300 Watts
Monoprice 300-Watt (150w RMS x2) Studio Audio Amplifier - Monoprice.com
300w Subwoofer Amplifier Board Low Pass Filter Subwoofer Pure Home Theater Active Subwoofer Amplifier - Home Theater Amplifiers - AliExpress