The **SunTube25 flat PVC** kit simplifies daylighting on PVC membranes by supplying the insulated upstand with pre‑applied PVC flashing. Bond the base, seat the crystal glass dome and run the rigid mirror‑finish tube to the ceiling diffuser for a soft, natural glow in small rooms. The dome’s scratch‑resistant glass sheds dirt and avoids yellowing under UV, so output stays consistent for years. With elbows and 60 cm extensions, installers navigate services and maintain reflectance through turns. For enhanced envelope performance, the optional EcoPower element adds glazed insulation to cut winter losses and summer gains. Compact aperture, clean finish and quick fitting—**SunTube25 flat PVC** is a smart way to add daylight where a window won’t fit.