Air Products and Chemicals, Inc, Allentown, Pa, offers the KeepCOLD service, which involves the filling of helium for MRI units. In addition the company offers the KeepCOLD Cryo-Shielding Maintenance Service, which involves change-out and/or repair of the MRI cold head, compressor, oil absorber, and other components. (800) 654-4567; www.airproducts.com/gases/keepcold.asp.