UniBond 2079110 Roof & Gutter Sealant, Long-Lasting Butyl Sealant for Roofing Applications, Waterproof Sealant for Outdoor Use, Flexible & Durable Roof Sealant, 1x504g Cartridge, Black

Very good product, stuck pvc to GRP

A couple of years ago I purchased and installed a nice patio cover at the back of my house, but I had to modify the supplied gutter to fit a restrictive space. I sealed the new joint with a product designed to weather seal motorhomes and caravans, but this week I noticed a slight leak at the joint and it was soon apparent that the sealant I used had gone hard and brittle and failed.I bought this Unibond sealant, with the expectation that it would remain flexible and therefore not harden and crack in the same way.As others have commented, there was a small amount of the product in the tube the wrong side of the inner piston, but the tube still appeared to be pretty full. I cleaned off this excess product before placing in a gun, then prepared the surfaces as directed. I applied masking tape to create a neat joint then started to apply it carefully. Although it’s of a fairly thin consistency, I found obtaining a neat result quite straightforward and it required very little tooling to get a great finish. It really does stick well, including to any tools you might have used. I also found that more of the product had seeped the wrong way down the tube and had made a bit of a mess inside my gun. The instructions say to remove unwanted product with white spirits, but I found that WD40 works just as well.24 hours later and the heavens have opened and it’s chucking it down, but my guttering is now perfect so this stuff has worked exactly as intended. OK, it’s a bit messy and required some extra care but for me it worked just great so it was well worth the extra effort.I hope you find my review helpful

Ensure product is a little warm, like airing cupboard or something before use.

Gungy muck that seals gaps! Really nasty sticky stuff. But don't be fooled, it won't stick to wet surfaces. Once stuck, though, it's very good. It remains gungy, flexible and messy, the point is that it stops water. Typical use would be to seal a piece of guttering with a broken clip that you can't renew. Place a bead in the joint then if it's black guttering a bead on every joint you can see. It isn't a cure-all for every situation, but it certainly has it's uses. And it's cheap.

The item had leaked therefore returned and received full refund

Good stuff

Good price and quick delivery, but, possibly my fault for not reading the description correctly, when I ordered it, as when I saw it was silicone I expected it to be clear and not black?

This is the worst gutter sealant I have ever used its messy,doesn't seal a simple clean dry gutter seal, whatmore can I say than absolute rubbish,awful to apply and more expensive than better products and then amazon said send it back for a refund.