MARTIN/F. WEBER-Bob Ross Oil Color. Bob Ross Products are manufactured with care, from the finest materials. They are individually evaluated for quality and performance so novices and experienced painters alike can achieve optimum results in the wet- on-wet painting technique. The Bob Ross Technique depends upon a special firm oil paint to achieve the desired effects. These oil colors are specially formulated for his wet-on-wet painting method and work well for other painting methods too! Quality ingredients insure permanence, color intensity, and professional results. This package contains 37mm tube of oil color. Available in a variety of colors each sold separately. Conforms to ASTM D4236. Made in USA.