Greenwood Airvac SF90T Extractor Fan 4″ (100mm) Centrifuglal with run-on timer. Mains 230v. Normally used in Bathrooms / En-Suites with longer duct lengths. This is a surface mounted fan. Suitable for wall, window, ceiling and panel installations Anti backdraught damper and pull cord insulation link. Backplate can be fully installed before fan and motor assembly are fixed to enable easy installation. Modern, stylish front facia design. Integral filter – easily removed for washing. Dimensions: 186mm wide x 142mm high x 142 deep. This is a direct replacement for the Greenwood Airvac S90T fan unit. This unit requires a permanent live, switched live + neutral (3 cores + earth) at the fan position for the timer functionality to operate correctly.