Double hung windows have two operating sashes; an outer upper sash and an inner lower sash. Both sashes operate by sliding up and down a track. Pneumatic balance systems are concealed to provide a clean appearance without unsightly vinyl tracks, or choose traditional weights and chains for an authentic replication. Caoba’s capability to reproduce products for landmark structures is a preferred specialty. Custom shapes to include round top, arched, and curved glass units can be crafted to your specifications. Available in our complete series of products, and can be stacked and mulled with other window and door types in various configurations.