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 wet surface to work into. These liquid oil colors serve as slow-drying base coats designed to provide a proper oil painting surface. These oil colors are specially formulated for his wet-on-wet painting method Quality ingredients insure permanence; color intensity; and professional results. This package contains one 236mL can of liquid oil paint. Available in a variety of colors: each sold separately. Conforms to ASTM D4236. Made in USA.