Ultra Mirco Micro Wet Grinder, Purple. 1.0 out of 5 stars 2. $224.30 $ 224. 30. Get it as soon as Tue, Aug 27. FREE Shipping by Amazon. Only 18 left in stock (more on the way). Stadea SWP104K Wet Concrete Polisher Grinder Kit with Concrete Diamond Polishing Pads - Wet Polisher Variable Speed for Wet Dry Polishing.