SWA EWC1 (R391) Plastic Compound. Specialised Wiring Accessories (SWA) is one of the UK's market leaders when it comes to manufacturing essential cable terminations, fixings, tools, and fastenings. With over 25 years of experience, SWA is a name associated with quality and reliability within the electrical industry. The SWA EWC1 plastic putty is an electrical weatherproof compound designed to protect electrical connections from moisture and corrosive vapours. This versatile product has impressive insulation properties that help prevent short circuits caused by darkness, making it ideal for a range of applications, including work on junction and conduit boxes. As the compound does not harden, shrink, crack, or peel when applied, it can be easily removed and replaced by hand. The putty has a wide operating temperature range from -20°C to +80°C and a Maximum working voltage of 1000V. Weight: 500g.