The L and R that indicate the two channels are located on the soft grommets that protects the signal cable where it enters the headphone shell. The letters are recessed into the grommets, and are very small. If they are too difficult to read, it may be easier to simply observe how the headphones are situated in the ears. The oval body of each in-ear, with the chrome stripe, should be away from the head, and be situated in the ear lobe, not stick out directly from the head.