Funko Pop! buy one get one 40% off

Amazon has a number of funko pops for buy one get one 40% off.
There isn’t an exact list of all items. I found Pops within a price range of 8-9 $ are eligible for this promotion.
Here are some good ones:
https://www.amazon.com/gp/product/B01MZZH14J/ref=ox_sc_sfl_title_2?ie=UTF8&psc=1&smid=ATVPDKIKX0DER?
https://www.amazon.com/gp/product/B01LEJD8W2/ref=ox_sc_sfl_title_3?ie=UTF8&psc=1&smid=ATVPDKIKX0DER?
https://www.amazon.com/gp/product/B01LEJD4GM/ref=ox_sc_sfl_title_4?ie=UTF8&psc=1&smid=ATVPDKIKX0DER?
https://www.amazon.com/Funko-POP-Anime-Yuichiro-Figures/dp/B01MQQ96LX/ref=sr_1_4?ie=UTF8&qid=1500407876&sr=8-4&keywords=funko+seraph+of+the+end?
https://www.amazon.com/gp/product…PDKIKX0DER
There are some add on items as well:
https://www.amazon.com/gp/product…PDKIKX0DER