405 Filleting Blend Adhesive Filler is a strong, wood-toned epoxy filler. Add it to your epoxy mix when making epoxy joints and fillets on naturally finished wood. It mixes easily with epoxy. This product helps you create smooth fillets that will need only a little sanding. Its color is a consistent brown. 405 Filleting Blend can be blended with other WEST SYSTEM Fillers to modify the shade of your epoxy mix.Â You can blend it into any WEST SYSTEM 105 Resin/20X Hardener combination, G/flex Epoxy 650, or G/5 Five-Minute Adhesive.