The MILWAUKEE® Jobsite Ear Buds Foam Ear Tip Kit - S is designed for use with the MILWAUKEE® REDLITHIUM™ USB Bluetooth® Jobsite Earbuds (2191-21). Milwaukee's replacement earbud tips is a direct replacement for the ear tips kitted with MILWAUKEE® REDLITHIUM™ USB Bluetooth® Jobsite Earbuds (2191-21).