Height-Adjustable T-Shaped School Chair, Groups No. (3)4-6, Flat-Oval Tube

This height-adjustable T-shaped school chair on a flat-oval tube is a student model for secondary school, covering height groups No. (3)4-6. The seat height sets to 350, 380, 430 and 460 mm, so a single chair fits pupils of different heights and "grows" with them — convenient for classes with a mixed age range.

The T-shaped frame is welded from flat-oval tubes 50×30×1.2 mm, 38×20×1.2 mm and 30×15×1.2 mm with a powder coating. The flat-oval profile gives the frame rigidity at a moderate weight. Height is adjusted with screws through the frame holes, and the seat is also adjustable in depth. The seat (380×360 mm) and backrest (380×200 mm) are made of bent-glued plywood 8.5–9.5 mm and finished with a clear, water-based lacquer; the corners are rounded. Plastic caps on the frame ends protect the floor.

The model suits secondary-school classrooms and study rooms where the ability to adjust furniture to a pupil's height matters.

• Overall dimensions: 380x420-455x775-855 mm, seat height 380–460 mm
• Height groups: No. (3)4-6, height adjustment (350/380/430/460 mm)
• Weight: 4.89 kg
• Seat and backrest: bent-glued plywood 8.5–9.5 mm, water-based lacquer, depth adjustment
• Frame: T-shaped, flat-oval tubes 50×30, 38×20, 30×15 mm, powder coating
• Frame colour: light green (RAL6018), grey (RAL7035), yellow (RAL1018), graphite (RAL7024)

How does a flat-oval tube differ from round or square? The flat-oval profile combines rigidity with a moderate weight and gives the frame a recognisable slim look; in terms of strength it handles classroom loads well.

What age is height group No. (3)4-6 for? A seat height of 350 to 460 mm is designed for middle-school pupils; the range lets one chair serve for several years as the child grows.