MARTIN/F. WEBER-Bob Ross Gesso. 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. Bob Ross Gesso contains pure pigments formulated in a 100% acrylic polymer emulsion which when dry produces a smooth; flexible; flat finish on artwork surfaces. It is ideal for the Bob Ross painting techniques with oil colors as well as other art media including acrylics; tempera; watercolors; ink; pencil; and more! This package contains one 473mL bottle of Gesso. Available in either White or Black: each sold separately. Conforms to ASTM D4236. Made in USA.