Best self-fusing silicone tape

Rescue Tape is the one I’d keep in the truck for a leak that has to stop now, and I’ve used it. This is the 1 in by 12 ft black roll, sold by Enovations when we checked. The 36 ft roll is the same tape.

It has the strongest published numbers here. Bond It’s data sheet lists a tensile strength of 950 PSI in its own test, against a military spec minimum of 700. It’s the only figure above 700 among these four, and it scored a 10.

Its cold limit is the lowest too. The sheet lists −85 to 500°F, with a continuous range of −76 to 392°F, a 10. Elongation tested at 800%, and the directions ask you to stretch it to at least double its length.

Standards scored a 10. Bond It says Rescue Tape meets UL Standard 510 and military spec A-A-59163, and it’s made in the USA.

The warranty is the clearest of the four. Bond It covers defects for one year from purchase, with a replacement or refund if you call with the receipt. That’s a 10. Shelf life is described as many years without a number, an 8.

The directions are specific. For a hose, wrap 3 to 5 layers and run 3 to 5 inches past the leak on each side. For a high-pressure leak, stretch it to the max. The first and last wraps should fully overlap.

Bond It also lists underwater repairs of hoses, pipes and connections among its uses.

Read its limits, too. Bond It writes that Rescue Tape isn’t designed to be a permanent repair, and that there’s no guarantee how long a repair will last. You can reposition it only in the first few seconds.

My call: wrap the leak, then plan the real fix with a clamp or a new fitting.

X-Treme Tape is the one I’d buy by the long roll, and I’ve used it. This is the 1 in by 36 ft black roll, sold by MOCAP, the company that makes it, when we checked. A 10 ft roll is also listed.

MOCAP calls it the original self-fusing silicone wrap and says it was first developed for U.S. military applications. MOCAP is based in Park Hills, Missouri, and says the tape is made in the USA.

Its spec sheet lists a minimum tensile strength of 700 psi and elongation of at least 300%, so it scored an 8 on tensile. The cold limit is −80°F for intermittent use, a 10. For continuous use, MOCAP lists −50 to 400°F.

Shelf life is its best number: 5 years from the date it was made, stored at room temperature. That scored a 10, and it’s the reason I’d pick this roll for a truck box that sits for months.

Standards scored an 8. The sheet says the product line is UL listed for use at not more than 600 V and 80°C, and that MOCAP has the ability to meet A-A-59163A. That’s a step short of saying it meets it.

The warranty covers defects in material and workmanship when it’s used as intended, but the sheet doesn’t give a term. That scored an 8.

It comes in more widths than the others: ½, ¾, 1, 1-1/2 and 2 in. MOCAP stocks 1 and 1-1/2 in widths in 10 and 36 ft rolls, and 2 in in 36 ft rolls.

The sheet also lists a cold brittle point of −63°F, water absorption of 3% at most, and a minimum tear strength of 60 ppi.

My call: buy the 36 ft roll if you’d rather have tape left over than run short.

Nashua Stretch & Seal is the one sold by Amazon itself, and I’ve used it. This is part 1743079, the clear 1 in by 10 ft roll. Amazon also sells the black roll.

Berry Global’s data sheet gives the numbers. It’s 20 mils thick, with a tensile strength of 700 psi and elongation of 300%. The tensile figure scored an 8, the same as X-Treme and Permatex.

It’s rated from −65 to 500°F, a 9 on cold limit. It’s UL 510 classified and meets A-A-59163 Types I and II, a 10 on standards. Berry says it insulates up to 8,000 volts per wrap.

One line on the sheet matters most for plumbing: you can apply it even in wet conditions for water- and air-tight seals. It’s also repositionable at first, so a crooked start isn’t wasted tape.

The package directions call for a two-thirds overlap on each wrap. Berry adds that it cuts away to remove and leaves no messy residue, so a stopgap wrap comes off clean when the real fix goes in.

Shelf life is where it lost points. The current Berry sheet lists 12 months from manufacture, a 7. An older Nashua sheet from 2014 said 36 months, but we went with the newer one. The sheet also says its data isn’t a warranty, so warranty scored a 5.

The clear roll lets you see the pipe under the wrap. Nashua lists clear, white, black, red and blue.

Watch the listing wording. It says the tape works on high pressure applications up to 700 psi. The 700 psi on Berry’s sheet is tensile strength, a pull test of the rubber, not a pressure rating for a pipe.

My call: it’s a good roll for a damp basement line, but buy it fresh rather than stocking up.

Permatex Self-fusing Silicone Tape comes from the gasket and sealant maker, and I’ve used it. This listing is a six-pack of part 82112, each a 1 in by 10 ft carded roll, sold by The Factory Depot when we checked. The single roll was unavailable.

Its data sheet names hoses and leaky plumbing among its typical uses. It meets military spec A-A-59163 and UL510, and it’s a class H insulator. That scored a 10 on standards.

Tensile strength is 700 psi and elongation 300%, an 8. The temperature range is −80 to 500°F for intermittent use and −50 to 400°F continuous, the same figures as X-Treme’s sheet. That’s a 10 on cold limit.

Its directions are the most detailed of the four. Clean dirt and oil off the repair area first. Use several layers for a leak, and overlap each wrap by about two-thirds while you stretch it. Fully overlap the last wrap and press it down.

Permatex says the repair is sealed right away in most cases and fully cures in 24 hours. Don’t try to reposition or reuse it. To take it off, cut across the width with a safety razor; it leaves no sticky residue.

One warning matters on a plumbing job. Permatex says not to use it in oxygen-rich systems or with chlorine or other strong oxidizing materials.

Shelf life isn’t stated, and the sheet disclaims all warranties, so both scored a 5. Permatex suggests storing it at 46 to 82°F in the unopened package.

The six-pack is the only way we found it in stock on Amazon, which works out to 60 ft of tape across six cards.

My call: put a roll in every truck, and keep it off chlorinated pool and spa lines.