The series 400 are professional white bristle brushes for oil and acrylic. Materials for the 400 series are hand selected and scrutinized at every step of the brush making process. The finest pure white bristle has natural flags. The hair has interlocking construction to preserve the natural inward curve of the bristle. All 400 brushes have a nickel plated brass ferrule. The perfectly balanced long handle is green lacquered hardwood with a gold tip.