XtraBond®350 - Low Modulus Neutral Cure Silicone

XtraBond®350 is a one component, low modulus, 100% high performance alkoxy cure silicone sealant that cures in atmospheric moisture. Manufactured for excellent adhesion to vinyl, glass, aluminum, wood, sheet metal and most common building materials without the need of a primer. XtraBond® 350 cures rapidly to form a durable tight bond.


  • Window Perimeters
  • Industrial Applications
  • Residential Applications


  • Indoor/Outdoor Use
  • Low Odor
  • Approved for Windows & Doors
  • Excellent Flexibility
  • Watertight
  • Excellent Adhesion to Glass
  • Mildew Resistant


Technical Specs

Skin Time 8 minutes
Tack Free Time 18 minutes
Cure Rate 1/4” Bead per 24 Hrs
Specific Gravity 1.03
Elongation @ Break 400%
Hardness (shore A) 23 +/- 5
Movement Capability +/- 25%
Peel Strength 29 psi
Bond Durability on Glass/Vinyl/Alumimum 25%
Tensile Strength 275 psi
Staining None
UV Resistance Excellent
Service Temperature -30 deg. F to 450 deg.



This product is offered in hundreds of colors using our Custom Color Matching & Mixing System.

For current color offerings, please visit the Online Color Matching Program.

NOTE: This product also qualifies for our Private Label Program.


The XB450 is available for the following industries

Packaging & Pictures

drum pail cartridge This product is available in the following configurations:

  • 10.1 oz cartridges: Twist-On Nozzles
  • 4.5 gal in a 5 gal pail
  • 52 gal in a 55 gallon drum

Other packaging is available upon request

Limited Lifetime Warranty

This product is guaranteed to give satisfactory performance if applied in accordance with the label directions. Liability to Premier Industrial Supply, Inc. (Premier) is limited to a full refund of the purchase price or product replacement if product is proven defective. Premier shall not be liable for loss or damage, whether direct, consequential or incidental. There are no other warranties expressed or implied including the implied warranty of merchantability or fitness for a particular purpose.