Abstract: A solenoid device for treatment of body tissue such as bones or other regions with pulsed signals comprises a flexible flat belt for encircling a body part or cast surrounding a body part containing tissue to be treated. The belt has a plurality of parallel conductors extending along its length and has its opposite ends offset by one or more conductor spacings. The resultant aligned conductor ends are connected together to form at least one continuous coil, with the resultant unconnected outer conductor ends at opposite sides of the belt comprising inputs across which a suitable electrical signal can be connected. An adjustment device or buckle is mounted on the belt to allow the diameter of the belt to be adjusted. The buckle traps a doubled over portion of the belt circumference which is adjustable in length to change the diameter of the device to closely fit the underlying body part or cast.