C – Parting bead. There are two parting beads positioned on either side on the sash box, working vertically from best to bottom concerning the sashes. Each and every half segment of a Ventrolla parting bead contains a draught-proofing procedure that faces the adjacent sash, forming a snug climate seal.  Putting in effective draught https://simonlxlbi.full-design.com/what-does-sash-windows-mean-78122387