Amazon.com: Pyle Waterproof Off-Road Speakers with Amplifier - 4 Inch 800W 2-Channel Marine Grade Waketower Speakers System Full Range Outdoor Audio Stereo Speaker for ATV, UTV, Quad, Jeep, Boat PLUTV42CH : Electronics
Juried Engineering LM2900N LM2900 Quad High-gain Frequency-Compensated Norton Operational Amplifier Op Amp Breadboard-Friendly IC DIP-14 (Pack of 10): Amazon.com: Industrial & Scientific
Amazon.com: Juried Engineering RC4136N RC4136 Quad Low Noise 30V Operational Amplifier Op Amp Breadboard-Friendly IC DIP-14 (Pack of 10) : Industrial & Scientific
Amazon.com: Major Brands LF444CN General Purpose Quad OP Amplifier, -18 Volt, 14-Pin, MDIP Rail, 3.3 mm H x 6.35 mm W x 19.05 mm L (Pack of 4) : Industrial & Scientific
Amazon.com: Compatible with 2002-2015 Dodge Ram Quad or Crew Truck Alpine Type S S-W10D2 Dual 10" Sub Box Enclosure with S-A60M Amplifier & 4GA Amp Kit : Electronics
Amazon.com: Juried Engineering TL064CN TL064 Quad Low-Power JFET-Input Operational Amplifier Op Amp Breadboard-Friendly IC DIP-14 (Pack of 5) : Industrial & Scientific
Amazon.com: Quad 707 Rear Stage Power Amplifier 2SD718 Loose Parts : Musical Instruments
Amazon.com: Major Brands LM324N General Purpose Quad OP Amplifier, -16-32 Volt, 14-Pin, Plastic Dip Tube, 4.57 mm H x 6.35 mm W x 19.3 mm L (Pack of 20) : Industrial & Scientific