This is the Idatalink Maestro SW steering wheel control interface module. This is a programmable module which will allow you to retain the use of your OEM equipped steering wheel audio controls (vehicle mist be equipped with steering wheel audio controls).
As taken from Idatalink's website: The ultimate in steering wheel integration, Maestro SW is compatible with over 1700 vehicle models with analog steering wheel inputs from 1998 to date and with most aftermarket radios. Maestro SW lets you retain original steering wheel functions AND assign a secondary ‘press & hold’ feature to the buttons of your choice! Best of all, SW is also the ONLY interface that lets you instantly create firmware for vehicles that are not included in the coverage list using a simple step-by-step web procedure.
Please visit www.idatalink.com for more information on programming and installation of this module.