Sika SikaBiresin® AP112 White Gallon BPO Hardener Required

The Sika SikaBiresin® AP112 White Gallon BPO Hardener Required is a professional-grade epoxy resin system engineered for marine repair, restoration, and structural bonding applications where durability and water resistance are non-negotiable. Whether you're reinforcing hull repairs, rebuilding transom sections, or sealing critical joints on your boat, this two-part system delivers the cured strength and chemical resistance that freshwater and saltwater environments demand. Boaters and marine craftspeople rely on this formulation to create repairs that outlast the vessel itself.

SikaBiresin AP112 is a cycloaliphatic epoxy resin that requires a separate BPO (benzoyl peroxide) hardener to initiate the cure cycle—a two-part system that gives you precise control over working time and final hardness. The white pigmentation makes it ideal for above-waterline repairs and cosmetic finishing where color matching matters, while the formulation itself offers excellent adhesion to fiberglass, wood, and metal substrates commonly found in boat construction. Once cured, this epoxy achieves high compressive and flexural strength, resists fuel, oil, and saltwater intrusion, and maintains its bond even under the stress cycles of engine vibration and hull flexing.

This gallon-sized container suits professional boat builders, restoration shops, and serious DIY anglers tackling multi-season projects or fleet maintenance. The one-gallon volume allows you to mix batches of varying size—from small structural repairs to larger lamination work—without overbuying or wasting material. Always pair this resin with the correct BPO hardener ratio specified by Sika; proper stoichiometry ensures full cure and maximum performance. For best results on fiberglass hulls, wood stringers, or bonding hardware, prepare surfaces thoroughly, use appropriate release agents or barriers if needed, and allow adequate cure time before launching or applying stress.