The EZ-Affordable Rechargeable Repair Machine, known as the EZ-ARRM, is a shoulder-length mechanical glove that comes standard with gyroscopic clocks (minimum two, one for Earth and one for the colony), and a wrist-mounted short range radio. The electrical components are charged using a ripcord. There is a thriving market for expansions of the EZ-ARRM; the device is in fact designed with possible expansions in mind.
The skill of Huberton's Manufacturing has made the EZ-ARRM an inexpensive and pervasive bit of technology, with the colony-wide adoption of it resting at 93%. The communications infrastructure of the colony relies on it, in that only the cities have enough range on their radios to communicate across great distances; locally, individuals are taught to forward all messages their machine receives to their own small radius, allowing messages to be transmitted with impressive reliability (though with the risk of significant lag).
The most common customizations purchased are a fire starter, a water purifier, a gyroscopic compass, and a wrist-mounted crossbow that shoots electric darts. There are, of course, any number of personal modifications that cannot be tracked as they do not have a purchase history. It is largely considered to be a mark of the upper class to have an underformed arm, as the EZ-ARRM is incredibly light weight and the more is does for you, the less you do for yourself.