Student Chair, T-Frame with Height Ratchet and Depth Adjustment, No. 4-7

This T-frame student chair on flat-oval tube is a model for middle and senior classes, adjustable for height groups No. 4-7. Its key advantage is the tool-free internal height ratchet: the height changes without screwdrivers or wrenches, and the position locks automatically at the preset height groups. Additional plastic clamp elements hold the chair firmly in place, so the furniture can be reset for a new class in just a few minutes.

The seat and backrest are made of bent-laminated plywood (8.5-9.5 mm) finished with a colourless water-based lacquer. The corners are rounded, and the seat depth can be adjusted to the pupil's height and posture. The T-shaped metal frame is welded from flat-oval tubes 50x30, 38x20 and 30x15 mm with powder coating. Height is adjustable across groups No. 4-7 (seat 380 / 430 / 460 / 510 mm; position No. 4 as an extra option). Plastic end caps on the frame ends protect the floor.

This is the base lacquered version; an HPL-finished version is also available.

• Overall dimensions: 410x460-500x(730)830-910 mm
• Height groups: No. 4-7 (seat height 380 / 430 / 460 / 510 mm; No. 4 optional)
• Adjustment: tool-free height ratchet with auto-lock + seat depth adjustment
• Seat: bent-laminated plywood 8.5-9.5 mm, water-based lacquer; seat size 400x400 mm, backrest 400x200 mm
• Frame: flat-oval tubes 50x30, 38x20, 30x15 mm, powder coating, T-shaped support
• Frame colours: grey (RAL7035), light green (RAL6018), yellow (RAL1018), graphite (RAL7024)

Why is a tool-free height ratchet useful? The height is changed by hand, without screwdrivers or wrenches, and the mechanism locks the chair on the required height group itself — a facility manager resets the furniture for a new class in minutes without a technician.

Why seat depth adjustment? The seating depth is set to the pupil's thigh length so the back rests against the backrest and the seat edge does not press under the knees.