2 pcs - Filter media bag, real super fine, 3 x 4 inches, Reusable 

Filter media bags for aquariums, freshwater or saltwater

This media bag is real fine and  works great
 for real fine Aquarium Chemical Filter media like Seachem Purigen.

If you media is a small as an iodized salt, this should work.

Reusable, good quality and affordable price.

Size:  3 inches by 4 inches height approximate.
Color is white. It has a string to close it.