The Sennheiser HD 450BT are closed-back, over-ear headphones designed to provide an immersive listening experience through a wireless connection. They feature active noise cancellation to help you focus on your music or calls by reducing ambient sounds, and they utilize 32 mm dynamic drivers that cover a frequency range from 18 Hz to 22,000 Hz. For connectivity, these headphones use Bluetooth 5.0 and support several codecs, including SBC, AAC, aptX, and aptX Low Latency, though you can also switch to a wired connection using the included 1.5 m detachable audio cable. Constructed from ABS plastic and PU leather, the circumaural design ensures a comfortable fit around the ears, while the total weight of 238 g keeps them light for extended wear. You can manage your audio and trigger virtual assistants like Siri or Google Assistant via the integrated touch controls. Power is supplied by a 600 mAh lithium-ion polymer battery that offers up to 30 hours of playback and can be fully recharged in 2 hours using the USB Type-C port. The package comes complete with a carry case and the necessary charging and audio cables, making them a practical choice for commuters or anyone who needs reliable wireless audio on the go.