Cobra Water Mixable Oil Colour Glazing Medium - A glazing medium formulated to aid in better paint flow. The amount of medium added affects the degree of transparency of the paint. This medium is very fat and may only be applied in the last few layers of a painting. It increases the degree of sheen and the durability of the paint film, but does not affect the drying time of the paint. It is vegetable oil based and can be thinned with water.