The mobile telephone service was introduced on April 10th 1987 (Showa 62). The service allowed calls to be made at anytime from anywhere. The phones were small and light (weighing approximately 700 grams) and included options such as long-life batteries and headsets. The service added to the practicality of the telephone. The service area was the same as for car telephones. The initial sign-up cost started from 298,300 yen with a deposit of 200,000 yen and a monthly usage charge of 23,000 yen.