- Zinc plated variable pitch spiral
- Metal zinc diecast fixing plug
- Tough ABS polymer outer casing available in Black
- Corrosion resistant stainless steel sash foot plate
The Whitco Window Spiral Balance 580 suits timber or aluminium double-hung windows in the 7.25-10kg sash weight range and is supplied with the standard foot attached. Its fully sealed construction uses an oil-tempered carbon steel torsion spring for smooth, balanced sash movement, with tension adjustable to suit the application. It also has shock-absorbing stops. It is recommended that the balance is supported in a 15mm x 15mm rebate.