BLITZU via Amazon has Lightening Deal: BLITZU Gator 320 USB Rechargeable LED Bike Light Set (Front & Back) for $15.97 – 50% off when you clip the coupon on the product page – $ 5.89 (lightning deal discount in cart) = $2.09. Shipping is free w/ Prime or on orders $25+.
Note: Coupons are usually limited to one per account.