5th Avenue NYC. IPN: Interlock Protein Network. Detangle, replenish and smooth. Smooth Lock Conditioner with Redken's exclusive Interlock Protein Network and smoothing heat fuse complex delivers almond oil and thermo-activated polymers to deeply nourish, protect and tame hair. Hair stays smooth and polished with luscious shine. Safe for color-treated hair. redken.com. Guaranteed only when sold in salons. Made in USA.