

🔧 Seal smarter, not harder — the ultra-flexible gasket maker pros trust!
Permatex 81724-12PK Ultra Blue RTV Silicone Gasket Maker is a sensor-safe, low-odor, and non-corrosive sealant designed for automotive applications. It offers eight times the flexibility of cork gaskets and three times the oil resistance of standard silicones, withstanding temperatures from -65°F to 500°F. Sold in a convenient 12-pack, it’s engineered for valve covers, oil pans, and other critical engine components, delivering superior durability and torque retention trusted by professionals.














| ASIN | B001REZ81O |
| Best Sellers Rank | #36,246 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #1 in Industrial Gasket Makers |
| Brand | Permatex |
| Customer Reviews | 4.7 4.7 out of 5 stars (273) |
| Date First Available | April 1, 2004 |
| Full Cure Time | 24 Hours |
| Global Trade Identification Number | 30686226817243 |
| Item Form | Paste |
| Item Weight | 0.01 ounces |
| Item model number | 81724-12PK |
| Liquid Volume | 3.3 Fluid Ounces |
| Manufacturer | Permatex |
| Manufacturer Part Number | 81724-12PK |
| Material | Silicone |
| Model | 81724-12PK |
| Number of Items | 12 |
| Product Dimensions | 1 x 3.8 x 8 inches |
| Surface Recommendation | Metal, Plastic |
| Unit Count | 40.2 Fluid Ounces |
| Water Resistance Level | Water Resistant |
D**S
best all purpose silicone on the market
50 yr mastertech here . ultra blue is my go to. . great stuff
S**N
Works great!
It's kept my valve cover from leaking and it's holding up great so far. You can't go wrong with ultra blue!
D**M
use as directed
Permatex products always get the job done
P**G
good product
I use this on oil pan gaskets and such. Worked great and does not harm anything. It has fixed several oil leaks on lawn mowers, cars and some other small engine work I have done.
K**E
Quality, affordable
I got this to replace the last tube I bought. It was only 1/2 used, but cured in the tube after 3 or 4 years in the garage. I found it to be very good to patch small holes-tears in my ATV seats. Did buy again. Will buy again. Oh.. makes good gaskets too!
D**R
Physics lab stuff
Surprise - this is one of two silicones that are useful in the lab as well as in the garage. This one doesn't emit ammonia in curing, (that's the sensor safe thing) and has a near zero vapor pressure once cured, making it valuable to seal tiny leaks in vacuum systems at a tiny fraction of the cost of the "pro" stuff sold to those who don't know this. Yes, it works on your auto, too. The other good one is the red hi-temp stuff (but for different reasons) - it's very hard to ruin the red stuff with heat....
A**R
the important part is the sealing and so far it's worked like a gem
Works well as a gasket. It was a bit harder to squeeze out of the tube than expected. I opened the hole up all the way and was laying a fairly decent sized bead, but still had to squeeze the heck out of the tube to get it to come out. This made it a little more difficult to lay a consistent, smooth bead across the surface. That said, the important part is the sealing and so far it's worked like a gem.
P**6
Amazing
Amazing product.
W**A
何時も愛用しています。
K**A
Excelente produto, cumple su función
J**E
ok
R**H
worked great
Trustpilot
5 days ago
3 weeks ago