Amazon.com: Airfrex Bluetooth Adapter Receiver with 2.5mm Jack for Sennheiser Momentum 2.0 ON Ear and Over Ear Headphones, Sennheiser Momentum 2.0 Headphone Cable Cord Replacement Connector Converter : Electronics
Sennheiser HD 518/558/598/580/600/650 Earpad Adapters — Mod House Audio
Sennheiser HD 518/558/598/580/600/650 Earpad Adapters — Mod House Audio
Sennheiser Replacement Lamella Ear Adapters For IE / CX Earphones - Small (5 Pairs)
Sennheiser NT 12-5 CW+ power adapter - 508899 - Laptop Chargers & Adapters - CDW.com