Complex sentence: Promotions Unlimited is the nation's leading provider of advertising and promotional material specializing in circular and coupon book advertising and providing everyday and seasonal merchandise for drug, variety, craft, grocery, hardware, and dollar retailers nationwide.
Split into simpler sentences: Promotions Unlimited is the nation's leading provider of advertising and promotional material. They specialize in circular/coupon book advertising and providing everyday and seasonal merchandise for drug, variety, craft, grocery, hardware, and dollar retailers nationwide.