Lambskin paint roller; 100% lambskin; Suitable for Water color and relief paints; Lambskin paint roller; 100% lambskin; Suitable for Water color and relief paints; If you'll be using oil-based paint, choose a roller cover made from natural fibers, such as sheepskin, lamb's wool, or mohair. You can also use a synthetic-fiber roller cover. Synthetic fibre roller sleeves are ideal for oil based paints such as gloss painting a flush door. The tighter the nap, the smoother the finish but be prepared to throw the smoother roller sleeves away as they are a nightmare to clean. Lambs wool used on a roller sleeve is perfect for emulsions. They hold more paint than synthetic sleeves and do not splash as much. The best choice is a roller sleeve from Mohair. This is ideal for most surfaces, when used with different length naps, and can even be used with varnish. Mohair is most often used with gloss paints and is ideal for oil based radiator paints.