Designed specifically for the unique challenges of workplace or leisure communication, SC-A0333 enables you to use your Sena device without the need for a motorcycle helmet. The SC-A0333 Earmuff Cradle converts a helmet headset to an over-the-head headset by attaching the main module of a 20S, 20S EVO, 30K or 50S to the earmuff cradle. By combining over-ear hearing protection with the communication capabilities of your Sena device and boasting a noise reduction rating of 28dB, you're sure to enjoy superior hearing protection with the same crystal-clear communication of your Sena device. The Sena earmuff cradle stands out with its durability and improved construction, providing a durable, long-lasting device. Moreover, its innovative design incorporates internal microphones that capture ambient noise, ensuring safety in high-traffic areas. Motorcycle Bluetooth communication device sold separately.