
Auto-Return Chair Columns
225, 265 and 305 mm total length options. Fixed height with auto-return rotation; no stroke or height adjustment.
SURFACE OPTIONS
Black and chrome.
Our standard finishes. Gold and other colours are considered as custom production requests.


Standard · Chrome

Auto-return · Black

Auto-return · Chrome
Retouched photographic product presentations; not technical references for a particular dimension or Class.
01 / PRODUCT RANGE
The right starting point
for every design.
Select a product family, then compare dimensions, Class and finishes.
Photographs represent the product family. Dimensions, interfaces and test scope are approved per model. Gold and custom finishes are assessed on request.
02 / TECHNICAL SUPPORT & CUSTOM PRODUCTION
Let’s select the right gas spring
for your chair.
We assess standard options using your base, mechanism and seat-height requirements, and prepare supply proposals for custom dimensions, functions, finishes and branding.
Requests are assessed with model, sample and order requirements.
Product selection
Select suitable options using stroke, target seat height, base hub and mechanism geometry.
Custom production options
Requests for custom lengths, lower steps, rotation functions, force and finishes.
Supply under your brand — OEM
Customer logos, product markings, labels and packaging. Scope and quantity are agreed in the quotation.
Samples and volume supply
Technical inquiry → model assessment → sample → customer approval → volume order.
PRODUCTION IN FOCUS
A closer look
at the process.
Short factory clips showing assembly, the production floor and storage.
Assembly line
12 sProduction floor
18 sStorage area
12 sVideos do not autoplay. Select play on the clip you want to watch.
03 / TECHNICAL CLARITY
Every specification.
Clearly defined.
Class, surface treatment and exterior finish are distinct specifications.
Class 1–4
Class must be evaluated with the relevant standard and test scope, not as a standalone load rating.
QPQ
A surface-hardening treatment for the inner tube, distinct from black paint, chrome or gold exterior finish.
Dimensions & traceability
Quotations, approved drawings and orders must reference the same model definition. Document scopes are assessed together with the relevant model and test conditions.
QUALITY DOCUMENTS
Quality certificates and test reports

TÜV Rheinland — Class 3

SGS test report — 2026

SGS test report — 2025
04 / PROJECT WORKFLOW
From specification
to serial supply.
- 01
Requirements
Drawings, dimensions and operating conditions
- 02
Model review
Standard configuration or custom assessment
- 03
Sample & approval
Sample scope and customer validation
- 04
Supply planning
Quantity, packaging and delivery terms

TECHNICAL DIMENSIONS
BN series.
14 stroke options.
Lengths in mm; force in N. BN codes identify the size series; Class, QPQ and finish are selected separately.
| Model code | Stroke | L1 | L2 | V | X | Y | Force (N) |
|---|---|---|---|---|---|---|---|
| BN-60 | 60 | 200 | 260 | 150 | 60 | 10 | 350-450 |
| BN-80 | 80 | 215 | 295 | 160 | 60 | 10 | 350-450 |
| BN-100 | 100 | 250 | 350 | 195 | 60 | 10 | 350-450 |
| BN-120 | 120 | 270 | 390 | 215 | 60 | 10 | 350-450 |
| BN-140 | 140 | 290 | 430 | 230 | 60 | 10 | 350-450 |
| BN-160 | 160 | 310 | 470 | 250 | 60 | 10 | 350-450 |
| BN-180 | 180 | 330 | 510 | 270 | 60 | 10 | 350-450 |
| BN-200 | 200 | 350 | 550 | 300 | 60 | 10 | 350-450 |
| BN-220 | 220 | 370 | 590 | 300 | 60 | 10 | 350-450 |
| BN-240 | 240 | 405 | 645 | 340 | 60 | 10 | 350-450 |
| BN-260 | 260 | 440 | 700 | 380 | 60 | 10 | 350-450 |
| BN-280 | 280 | 475 | 755 | 420 | 60 | 10 | 350-450 |
| BN-300 | 300 | 510 | 810 | 460 | 60 | 10 | 350-450 |
| BN-320 | 320 | 545 | 865 | 500 | 60 | 10 | 350-450 |
All lengths in mm; force in N. L1: compressed length; L2: extended length.
L2 for BN-60, BN-80 and BN-220 is calculated as L1 + stroke; not a measured production value.
BN-160/240 are interpolated; BN-280/300/320 are extrapolated design estimates. X/Y and force on these rows are series references.
Calculated values are not measured production data. Force is not a user-weight capacity rating.
BN codes identify the size series. Class, QPQ, finish and mounting geometry are selected separately.
05 / TECHNICAL RESOURCES
One product.
One technical definition.
Model codes, dimension definitions and product families must remain consistent across catalogs, quotations and technical sheets.
Technical dimension table↗Request a drawing / test document↗Request the technical drawing and available test documents for your selected model.
PRODUCT SELECTION GUIDE
Clear specifications.
The right selection.
Start with product function and mounting dimensions, then assess the chair application.
Are stroke and total length the same?
No. Stroke is the travel during height adjustment. Total length is measured between the reference points on the drawing. Specify these dimensions separately.
What do 100 and 10 mean in market terminology?
Market terms may refer to a 100 mm stroke as 100 or 10. Our technical dimensions are in mm. Identify orders using a model code and an explicitly stated stroke.
How do I select Class, QPQ and finish?
Class is a technical configuration. QPQ is an inner tube treatment considered for Class 3 / 4. Black and chrome are exterior finishes. Gold and other colours are custom-production requests.
Do D50 and D60 indicate diameter?
In this product range, D50 and D60 mean a 50 mm or 60 mm lower-step height. They do not specify diameter. Check base hub position and mechanism height together.
Why is no stroke listed for auto-return columns?
Our auto-return columns have fixed height. Select by 225, 265 or 305 mm total length. The visible inner tube length is 70 mm. Rotation angle and mounting dimensions require confirmation against the model drawing.
Can one model be used in different chair types?
Yes. Executive, task or operator chair labels alone do not determine the gas spring. Assess the base, mechanism, cushion height, interfaces and operating requirements together.
LET'S REVIEW YOUR PROJECT
Share your
technical requirements.
Enter a model code, or describe the dimensions and operating requirements of your custom design.
Office
Topçular Mah. Osmangazi Cad. No:2 İç Kapı No:18, Eyüpsultan / İstanbul / TÜRKİYEOffice Map ↗Warehouse
Warehouse hours: Monday–Friday 09:00–17:00. Closed Saturday and Sunday.
Yeşilbayır, Yapı Cd. No:42 D:44, 34000 Arnavutköy / İstanbulWarehouse Map ↗Send your inquiry using the form. We respond during business hours.