Audio cable (3.5mm stereo jack to 3.5mm stereo jack) for your Sony ZS-S4iP Boom box CD speaker dock.
Directly connect iPhones, smartphones with the 3.5mm headphone socket to your Sony ZS-S4iP Boom box via the Aux input on the rear of the speaker.
Note: For iPhone 7, 8, 10, X etc without headphone socket, use the Apple Lightning to 3.5mm headphone adapter included with some iPhones or available from Apple.