Make sure all items are sold and shipped by Rosewill, or discount + free shipping will not apply. On the 15-Piece Rosewill RTK-015 Computer Tool Kit product page, 'clip' the 30% coupon and add item to your shopping cart. https://amzn.to/2V285aA Add the 10oz Rosewill Compressed Gas Duster to your shopping cart. https://amzn.to/33i5M7x Add the Rosewill Anti Static Wrist Strap Band to your shopping cart. https://amzn.to/3l7i1Kc Make sure you select the sold/shipped by Rosewill option (not sold by Rosewill / fulfilled by Amazon) Discount will apply at checkout. Complete your order. Must be logged in to clip coupons; coupons are typically limited to one per account.