Offering a powerful, bass driven stereo sound with greater clarity and improved dynamics over standard earbuds are the Sennheiser CX 300 II in ear headphones. The various sizes of ear adapters (S/M/L sizes) provided in the package allow for a customized fit as well as exceptional noise blocking capability.
https://www.amazon.com/Sennheiser-CX300-II-Discontinued-Manufacturer/dp/B001EZYMF4

