Sennheiser HD 4.40 BT Bluetooth Wireless are a compact full size, matte black, over ear headphone with an ear opening just large enough to fit around ear while minimizing overall size and bulk. The earpads are very deep and plush, providing great comfort and excellent noise isolation - likely the best passive isolation we've experienced in a full sized headphone.
Battery life is an excellent 25 hours! Headband is thin with a rubber cushion. HD 4.40 BT folds up small.
Bluetooth sound is very good, better than we expected at this price, with a good balance of full bass and nice clarity. Compared with other bluetooth models, these can play LOUD, so perfect for gym rats, with older recordings, or classical recordings that are recorded at very low levels. Carry bag included, audio cable, charging cable, 2 year warranty.
Innerfidelity.com 2017:The HD 4.40 BT is elegantly styled and very well built. Comfort is quite good...Sound is warm, smooth, and enjoyable.