Review (1/5): Don’t use the bamboo holder unless you want a moldy mess
I ordered 2 containers, one for shampoo and one for the conditioner. I’ve been using them for about a month, shampooing my hair every 2 days. By the end of the month the containers were basically all black from molds. This picture is what it looks like even after I cleaned the containers. Save yourself a trouble and just use plastic/metal bar soap holders.