West System G/Flex 650-K Aluminum Boat Repair Kit, 4 oz.

West System G/Flex 650-K Aluminum Boat Repair Kit — 4 oz.

The G/Flex 650-K is a complete, ready-to-use repair kit built around G/Flex 650 flexible epoxy — specifically formulated for bonding aluminum, making it the go-to solution for aluminum hull repairs, jon boat patches, and metal-to-fiberglass joints. Everything you need for a clean, professional repair is included in the box.

What's in the Kit

• 4 fl. oz. G/Flex 650 Resin
• 4 fl. oz. G/Flex 650 Hardener (8 fl. oz. mixed epoxy total)
• 2 reusable mixing stick/applicators
• 2 × 12 cc syringes for precise dispensing
• 4 grams adhesive filler
• 4 mixing cups
• 1 pair disposable neoprene gloves
• 4 alcohol cleaning pads
• Complete handling and repair instructions

Key Features

• Engineered for aluminum bonding — G/Flex 650 penetrates and bonds aluminum oxide surfaces that standard epoxies struggle to grip
• Flexible and impact-resistant — 150,000 PSI modulus absorbs vibration, shock, and thermal expansion without cracking the joint
• Waterproof and fuel-resistant cure — permanent bond holds in bilge, below the waterline, and in wet environments
• 1:1 mix ratio — equal parts resin and hardener; syringes included for clean, accurate dispensing
• 45-minute working time at room temperature; initial cure 7–10 hours, full cure 24 hours
• Compatible with WEST SYSTEM® fillers and additives — can be thickened or used to wet-out fiberglass tape over repairs

Best Use Cases

• Patching cracks, pinholes, and stress fractures in aluminum hulls and jon boats
• Bonding aluminum fittings, brackets, and hardware to aluminum or fiberglass surfaces
• Sealing riveted seams and lap joints on aluminum boats
• Metal-to-fiberglass bonding where flexibility is required
• Field repairs where a complete, self-contained kit is needed

Also Available In

• West System G/Flex Epoxy Bottles, 8 oz.
• West System G/Flex C65032 Epoxy, 32 oz.
• West System G/Flex Epoxy 2 Gallon Kit
• West System G/Flex 655 Epoxy Adhesive Repair Kit, 2 Quarts
• G/Flex 655 Epoxy Adhesive Repair Kit

Parts Desk Insights

The 650-K is the right choice when the repair involves aluminum — not just because of the included supplies, but because G/Flex 650 is specifically optimized for aluminum oxide adhesion in a way that standard 655 or 105-series epoxy is not. The kit format (syringes, gloves, alcohol pads) makes it ideal for a single focused repair job without needing to source accessories separately. For larger aluminum repair projects or ongoing maintenance, consider stepping up to the 8 oz. G/Flex bottles or the 32 oz. size for better value per ounce. If the repair also involves fiberglass or wood substrates, the G/Flex 655 2-quart kit is the more versatile option.