Both sides of the sponge can be used.
24K Dry Cosmetic Beauty Brush Cleaner none 3x1x3 24K Dry Cosmetic Beauty Brush Cleaner 3x1x3 none Dimensions: 3.5 ounces Made in China This brush cleaner eliminates washing and drying time by simply gliding the brush over the surface of the sponge for effective cleansing and powder pigment removal..