Per purchase, Hammacher Schlemmer accepts up to four promotional certificates. You can apply coupons during checkout, but the number of promo codes you can use may be limited depending on your device. That means you can use numerous Hammacher Schlemmer coupons and discounts on the same order, however there are certain limitations. https://www.mysavinghub.com/store/hammacher-schlemmer-promo-code