Loctite 638 Retaining Compound Considered as a high strength retainer, this Loctite 638 Retaining Compound is ideal for metal bonding applications. It is used for the bonding or filling gaps(approx. 0.25mm) of cylindrical fitting parts. This product is processed with the use of balanced chemical composition and modern methodology by skilled professionals. Available in airtight packaging, our provided product is easy and safe to apply. This product is reckoned for standard shelf life and toxic compound free composition.