West System G/Flex 650 Epoxy – 2 Gallon Kit (655-C6502G)
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
West System G/Flex 650 is a toughened, flexible liquid epoxy engineered for permanent waterproof bonding of fibreglass, ceramics, metals, plastics, and difficult-to-bond or damp woods. Unlike standard epoxies, G/Flex 650 has a modulus of elasticity of 150,000 PSI — making it more flexible than conventional epoxy or polyester, yet significantly stiffer than adhesive sealants. This balance allows it to absorb the stress of expansion, contraction, shock, and vibration, making it particularly well-suited for bonding dissimilar materials that move independently.
G/Flex 650 uses a simple 1:1 mix ratio by volume, provides 45 minutes of working time at room temperature, reaches initial cure in 7–10 hours, and achieves full cure in 24 hours. It can be modified with West System fillers and additives, and used to wet out fibreglass tapes and fabrics. This 2-gallon kit includes two 1-gallon cans (resin and hardener).
Note: This product is classified as a hazardous material. Shipping restrictions may apply — please contact us before ordering if you have questions about delivery to your location.
Key Features
- Toughened, flexible epoxy — absorbs shock, vibration, and thermal movement
- Bonds fibreglass, ceramics, metals, plastics, and damp or difficult-to-bond woods
- 1:1 mix ratio by volume for easy metering
- 45-minute working time at room temperature
- Initial cure: 7–10 hours / Full cure: 24 hours
- Compatible with West System fillers, additives, and fibreglass fabrics
- 2-gallon kit: two 1-gallon cans (resin + hardener)
G/Flex Family – Other Sizes & Formats
- West System G/Flex 650 Epoxy – 8 oz. (2 x 4 oz. bottles) — small size for repairs
- West System G/Flex C65032 Epoxy – 32 oz. (2 x 16 oz. bottles)
- G/Flex 655 Epoxy Adhesive Repair Kit – 2 Gallons — thickened adhesive variant in bulk
- West System G/Flex 655 Epoxy Adhesive Repair Kit – 2 Quarts
- West System G/Flex 650-K Aluminum Boat Repair Kit – 4 oz. — targeted repair kit for aluminium
Related Products
- West System C209SB Extra Slow Hardener – 1.24 L — for traditional two-part epoxy systems
- West System Plastic Spreaders, 12-Pack — for spreading and fairing epoxy
- West System Epoxy Injection Syringes, 12-Pack — for injecting epoxy into tight spaces
Parts Desk Insights
Best Use Case: The G/Flex 650 2-gallon kit is the right choice for professional yards and serious boatbuilders doing large-scale bonding work with dissimilar materials — particularly aluminium-to-fibreglass, teak-to-fibreglass, or any joint subject to thermal cycling or vibration. The 1:1 ratio makes metering straightforward without pumps. Flag the hazmat classification at point of sale — ground shipping only, and some locations may not be serviceable. For smaller quantities, direct customers to the 32 oz. kit or 8 oz. bottles. For a pre-thickened cartridge format, recommend the West System Six10 Thickened Epoxy Adhesive.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.