The GT Bow Constrictor is a spring device designed to strengthen the seal of a sash between the lock and hinge sides on large top-hung windows. It features an acetal moulding set and two sizes of spring steel components, fitting all 13mm and 17mm stack height PVCu systems. When the window is closed, the Bow Constrictor enhances compression between sash and frame, even allowing for night vent locking positions when required.

Key Features:

• Enhances sash compression for improved sealing
• Designed for 13mm and 17mm stack height PVCu systems
• Supports night vent locking positions
• Manufactured in the UK from durable materials
• Simple, face-fixed installation with no routing required