Features: You will get a great sound wearing your helmet of which with this speakers inside when you're riding a motorcycle or a motorbike. Very easy to install，the soft speakers can be attached to the inside of your helmet by adhesive stickers， there is an on/off button and a volume controller on the cable，an extension cord is included as well. The helmet speakers have a 3.5mm standard plug and will work well with your MP3，MP4，GPS，Iphone，Cellphone，etc. which has the same jack Specifications: Connection: 3.5mm jackSpeaker dimensions (diameter x width): 60 x 10mm (2.3 x 0.4")Attached cable length: 92cm (36")Extension cord length: 94cm (37")Total cable length: 186cm (73")Color: BlackPackage includes: 1 sets of headphone