Bostik S21 is a professional-grade, low-modulus acetoxy silicone sealant engineered for perimeter glazing, frame sealing, and sanitary joints. Formulated with an advanced mould-resistant additive, it provides durable resistance against cracking, shrinking, and discolouration in high-humidity areas.
This versatile sealant offers exceptional UV and weather resistance, accommodating up to 20% joint movement for both interior and exterior applications. It adheres reliably to painted timber, non-ferrous metals, tiles, sanitary ware, and kitchen worktops.
Brand
Bostik
Model
S21
Product Type
Silicone Sealant
Cure Type
Acetoxy
Volume
310 ml
Movement Accommodation
Up to 20%
Modulus
Low Modulus
Application
Interior & Exterior
Resistance Properties
Mould, UV, Weather, Shrink, and Crack Resistant
Standards
BS EN 15651:2017
Weight
0.4 kg