Epson TM-C3500 Spare-In-The-Air exchange program (SITA) is an extremely affordable service solution for companies that cannot afford to have their systems out of service for longer than 24 hours. Must be purchased with new printers within the first 30 days of the factory one-year limited warranty period. This quick, overnight replacement program bridges the gap between the turn-around time of depot repair and the higher cost of on-site service. Make one phone call to Epson and a replacement unit is express-shipped overnight to arrive the next day. Then just return the damaged unit to Epson. It's that easy. And shipping both ways is always on us.