Panel Mount 1/8 / 3.5mm Mono Connector : ID 4361 : $0.95 : Adafruit Industries, Unique & fun DIY electronics and kits
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Mono Audio Adapter - 3.5mm Plug to RCA Jack | Computer Cable Store
3.5 mm. Minijack mono male connector, plastic
Amazon.com: RFAdapter 3.5mm Mono Right Angle Male to Female Auxiliary Audio Cable, 2-Pack : Electronics
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