Customers in the United States and Canada can now get a free Touch Cover or Type Cover with the purchase of a Surface RT tablet. Touch Covers usually cost $120 (or $130 for limited edition versions) and Type Covers usually cost $130. The Surface RT costs $499 with 32GB of storage, or $599 with 32GB.

Microsoft’s U.S. blog post doesn’t say when the “limited time” offer ends. However, a similar offer for customers in Europe that kicked off a couple weeks ago is scheduled to end on June 30.

Meanwhile, Microsoft also will offer major discounts on both Surface RT and Surface Pro at its TechEd conference next week. Attendees can snag a Surface RT for $100, or a Surface Pro for $400. (Don’t get overly excited. The conference itself, an educational event for IT professionals, costs a cool $2,195 to attend.)

The timing may not be a coincidence. Microsoft is holding its Build developers conference starting on June 26, and rumors have hinted at the announcement of new Surface tablets with 7-inch to 9-inch displays. Microsoft may be trying to unload some of its inventory as it prepares to refresh the Surface line.