CT1 Underwater Marine Sealant (Black)

CT1 Black Sealant & Construction Adhesive

When you need a seal that grips hard and stays flexible, CT1 Black delivers. It bonds to most common building materials without additional fixings and keeps its shape under pressure – no cracking, no shrinkage.

CT1 is odourless, easy to apply and works in wet or dry conditions, including underwater repairs. Its UV resistance helps the colour stay true, making it a tidy choice where black finishes matter.

Built with TRIBRID® technology, CT1 combines sealing and bonding in one cartridge, with strong adhesion across metals, masonry, glass and timber.

Why it works

• High-strength bond to most materials without screws or fixings
• Flexible finish that won’t crack or shrink over time
• Works wet or dry, even for underwater repairs
• UV-resistant for long-lasting black colour
• Vibration-resistant for areas that move or flex
• Hygienic – resistant to fungal and bacterial growth
• Odourless formula with no solvents or isocyanates
• Versatile for repairs, sealing and emergency fixes

Suitable for

• All metals, including lead
• Glass and mirrors
• Wood, MDF and timber products
• Fibreglass and carbon fibre
• Tiles and concrete
• Most natural stones (non-staining)
• Most synthetic materials and plastics
  • Not suitable for PP, PE or PTFE

Common uses

• Sealing leaks and joints
• Bonding trims, panels and fittings
• Bathroom and shower sealing
• Marine and saltwater environments
• Emergency repairs indoors or outdoors

Important notes for pond use

• Allow CT1 to fully cure before contact with pond water
• Do not use on polypropylene, polyethylene or PTFE fittings
• Always follow manufacturer curing and safety guidance before use

Colour: Black
Type: Hybrid sealant and construction adhesive

If you’re fixing, sealing or patching around the garden, pond edge or filter area, CT1 Black offers a strong, flexible hold with a neat finish.