Amazon with yooshome has the QUI RF 2.4GHz Presentation Clicker for PowerPoint with Volume Control for $20 - $9 off with coupon code YJFCPJIG at checkout = $11 with free shipping on $35+ or with Prime. Currently is #1 best seller in office presentation pointers on Amazon. 

Amazon promo codes don’t always work on the first attempt. Try refreshing the page and re-entering the code.