1byone via Amazon offers the 1byone LED Hydroponic 12-watt Light Bulb, model no. 322NA-0001, for $15.99. Coupon code "K6CV5Y9O" drops it to $11.83. Plus, Prime members bag free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $6.87.) That's $8 off list and the lowest total price we could find. It consists of nine red LEDs and three blue LEDs and has fits E27 sockets. Deal ends November 30.