Valid through 3/31/12 in Staples® U.S. stores only. Discount applies to Pentel Mechanical Pencils, Lead Refills and Erasers only. Limit one per customer. While supplies last. Each item purchased can only be discounted by one coupon, applied by cashier in order received and prior to tax. Coupon not valid if purchased or sold and must be surrendered. No cash/credit back. Not valid on prior purchases or purchases made with Staples® Procurement Cards or Convenience Cards.