EnduraflexTM RC524WCChlorobutyl Soft EnduraflexTM white, soft, cured chlorobutyl. Not recommended for NaOCl (bleach) or hydrofluoric acid (HF) service. FDA compliant. For more information about this product, complete the form below or call 800-321-5583. Specs: Application: Food Applications, Reagent Grade Acids Durometer: 40 to 55 A PDF Downloads: Spec Sheet (PDF) SDS (PDF) Notice: JavaScript is required for this content.