• Over 6000 productsOver 6000 products
  • Next Day Delivery on orders confirmed before 2pmNext Day Delivery on orders confirmed before 2pm
  • 8 depots for national coverage8 depots for national coverage
Product Information
Technical Datasheet
Safety Datasheet


AlphaChem Silicone 303 is a premium low modulus, neutral cure silicone for expansion joints and perimeter points. Fast curing, low meko formula with excellent adhesion to different substrates. With excellent tooling and added anti fungal compound and uPVC adhesion promoters.


  • For building and construction joints with high movement
  • For perimeter sealing of window and door frames (uPVC, wood and aluminium)
  • For weather sealing and joint sealing of in-fill panels


  • Weatherproof
  • Anti-fungal
  • Permanently elastic
  • UV stable colours
  • Added uPVC adhesion promoters
  • Low meko
  • Compatible with metal and alkaline surfaces