TR001/TR003/TR004 – Towel frameTowel frames TR001, TR003 and TR004 are made of stainless steel. They are accessories for infrared glass, mirror and stone heaters. Add the frame to your Sundirect heater to use it for towel drying. You can add one frame to a GD450 and MD300 mirror and two frames to other glass and mirror panels. For stone heaters you can add up to three towel frames. TR001 is suitable for GD-Plus glass and MD-Plus(MD300/450) mirrors TR004 is suitable for TH400-V2 TR003 is suitable for TH600-Pro/STONE800-Pro. here installation instructions!