Shenzhen E-Fortune Digital Mfy Ltd produced a digital key chain with the functions of an alarm clock and calendar. They are currently working an a model that will have the capacity to play music. The issue with the digital key chains is their small size. Functionality is limited because of this. However, companies are aiming to offer customers more options. Besides music, Depo Manufacturing Company, is working on a plug and play model with increased storage capacity. Another issue that limits functionality is demand and market price. Market prices for digital key chains start at $6 up to $20. The $20 price tag is one that few customers seem willing to pay. $10 is the median price for these products. Features like blue-tooth and WiFi could be integrated but will not be due to the market price. Despite low prices, demand for these products has remained steady so new innovations will always arise. It takes a manufacturing company 1 to 3 months to produce a new model. A model currently on the market that incorporates digital images with an MP3 player is the digital photo frame produced by Wenzhou Times Company, Ltd. The digital photo frame comes with a metal chain so that it could be used as a key chain.