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This heavy-duty brush is made with an injection molded plastic handle and tough synthetic bristles that stand up to years of heavy detailing use. Nifty Car Interior Detailing Brush | Car Detailing | Chemical Guys Super stiff synthetic bristles with an ergonomic handle transfer powerful scrubbing action into the toughest set-in stains and debris.. The Chemical Guys Induro 7 Heavy Duty Nifty Carpet & Upholstery Brush scrubs intense dirt, stains, and debris from carpet, floor mats, and upholstery.