carbine slot for coarse grinding, ceramic slot for fine polishing, looks like Lansky Blademedic.
Get coupons, create price alert or check price history out! Best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. Well, there is one coupon available right now.
Link: Banggood product page
1. ($8.82): BGherra
you should apply the coupon in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): bgsport, TTxBG10, TOOLS15, 502C6B, BG2020NS, BGMPB2020, BGAFF10OFF, bGhOnEy10, BgcLuBofErtA10, BG592dca
(system checks these coupons on every price check (like once per 24 hours), but you can check them out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for Outdoor Knife Sharpener? There we go. The lowest price was: $3.55.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).