Designed for SBS or APP roof builds, **SunTube25 flat bitumen** ships with an insulated upstand pre‑finished in bitumen so detailing ties neatly into the membrane. A crystal glass dome collects daylight without discoloration and the rigid, ultra‑reflective tube carries it down with minimal loss to the easy‑click diffuser. The 25 cm format suits compact rooms; add elbows and extensions to reach through services or deeper build‑ups. Where thermal control matters, integrate the EcoPower glazing element to improve U‑values and sound attenuation. With **SunTube25 flat bitumen**, you gain reliable daylight from a small opening, a clean interior look and an install that respects the roofing system.