Structural Polyester Bonding Putty - Marine Grade, Fiber Reinforced Filler, Smooth Spreading & Sag Resistant - Ideal for Boat & Automotive Repair on Fiberglass, Wood - Quart Kit

First and foremost the product is everything the manufacturer says it is and more...The price-point of the product might lead you to believe it because it's not as good as the big -name products - Not true. It's some of the best and here's why ... When catalyzed correctly you can get a working life of 45min to an hour, very helpful when working on large or complex surfaces. It's easily as hard as any epoxy on the market but CAN be used with gelcoat, unlike epoxy. The gray color cures much lighter, almost white... It sands well, without voids and accepts paint and gelcoat well... Some reviewers have complained about it's clear color making hard to determine if it's mixed well... if this is a problem a tiny portion of pigment for rosin or gelcoat alleviating that concern... It's hard, so only use the amount you need and clean off all excess before it hardens and save money and time when sanding...

Outstanding product, very strong. Just as advertised. Mixes well and has a reasonable working time. I have order it three times now for various marine projects.

I used this for fixing some structural cracks and dings in a fiberglass canoe. Works very well. Dries crazy hard. Don't overfill because it is quite hard to sand. Not a fairing compound.

I found this a little difficult to use because the MEKP is clear and the putty doesn't change color when catalyzed. Because the putty is not a liquid, it is difficult to tell what volume of putty you are mixing up. I had no problem measuring the MEKP, but was guessing on the quantity I needed. Old fashioned Bondo for cars comes with a paste hardener that is colored. That lets you achieve a uniform color to know when it is mixed well enough. This putty is white and the MEKP is clear and runny, so it was a blind guess to know if it was properly mixed and if the ratio of 1% MEKP was achieved. It seemed to work well.

I had some structural repairs to do on a boat hull project that needed to be done before laying glass.It's thick & can be cut with polyester resin,to flo out smoother if need be. The longer it cures,the harder it is to sand. Overall, the gallon came with a lid retainer & nicely wrapped in bubble wrap. Product works great & I'm definitely happy with this purchase & would recommend

Excelente producto

Used it to bond in stringers and knees and make the nice fillet before laminating in a mini speed boat. Worked perfectly.

worked very well