Sihoo M18 Ergonomic Office Chair with Headrest, Black vs Steelcase Series 1 Task Chair, Licorice, Carpet Casters
These are side-by-side facts taken from each product guide: published specifications, strengths and caveats as their sources state them. This page is not a test, a ranking or a verdict about which model is better.
Sihoo M18 Ergonomic Office Chair with Headrest, Black
A padded seat with a mesh back at a 17 to 21 inch seat height
The M18 pairs a padded W-shaped seat with a mesh back, a sliding two-way lumbar support and a height-adjustable headrest. Sihoo rates it to 330 pounds. The armrests move up and down only, and the sheet in the box mentions a one-year warranty where the listing promises three.
Published specifications
- Maker page: 28 W x 27 D x 44-51 in high, 37.1 lb, 330 lb maximum load
- Listing chart: seat 51 cm (20 in) wide, seat height 44-54 cm (17-21 in)
- Maker page: seat depth 17.91 in, maximum hip width 20.08 in
- Armrests adjust up and down only; headrest moves 3.9 in and pivots 45 degrees
- Manual: six functions, eight assembly steps, hex wrench and spare screws included
- Warranty: manual mentions one year, listing and maker page say three years
Strengths
- Sihoo publishes an exact-model installation guide and a matching product page
- Lumbar support adjusts both up and down and in and out
- Six separate adjustments, assembled with one included hex wrench
Caveats
- The guide in the box mentions a one-year term while the listing promises three years
- Armrests have no width, depth or pivot movement at all
- Listing model number field names a different Sihoo product entirely
Read the full Sihoo M18 Ergonomic Office Chair with Headrest, Black guide
Steelcase Series 1 Task Chair, Licorice, Carpet Casters
Carpeted rooms, because this build ships with hard casters
The Licorice 3D Microknit version of Steelcase's Series 1, ordered with four-dimensional arms, adjustable lumbar and carpet casters. The back tension dial has three settings, the seat adjusts for height and depth, and Steelcase's warranty gives mechanisms, cylinders, foam and casters a 12-year term.
Published specifications
- Model code 435A00-5T21-5S26-6205-4ARM-LUM-CC: Licorice, black, 4D arms, lumbar, carpet casters
- User guide: tested to 300 lb, meets ANSI BIFMA; maker page now says 400 lb
- User guide: hard casters for carpet, soft casters for hard floors
- Back dial: upright lock, full recline with weight-activated tension, plus boost
- Amazon table: seat height 21.5 in, seat depth 17.75 in, item weight 29 lb
- Warranty: 12 years on mechanisms, cylinders, arm caps, foam, casters and glides
Strengths
- Seat height, seat depth and a three-position tension dial all adjust without tools
- Steelcase publishes the full component warranty table and the user guide
- Ships ready to assemble, and the guide's two-to-three-inch knee rule sets seat depth quickly
Caveats
- The listing says Carpet Floors in the title but Hard Floor in the item details
- The packed user guide says 300 pounds while the current maker page says 400
- The Americas warranty document excludes retail consumer purchases and unauthorised sellers
Read the full Steelcase Series 1 Task Chair, Licorice, Carpet Casters guide
How to choose between them
Choose the Sihoo M18 Ergonomic Office Chair with Headrest, Black if your situation matches: A padded seat with a mesh back at a 17 to 21 inch seat height. Its main caveat: The guide in the box mentions a one-year term while the listing promises three years.
Choose the Steelcase Series 1 Task Chair, Licorice, Carpet Casters if your situation matches: Carpeted rooms, because this build ships with hard casters. Its main caveat: The listing says Carpet Floors in the title but Hard Floor in the item details.
Both entries repeat what each guide records. Confirm the model, included parts and availability on the current listing before ordering.
Primary sources
- Sihoo product installation guide naming Model M18 (maker PDF supplied on the listing) Source for Sihoo M18 Ergonomic Office Chair with Headrest, Black
- Sihoo US store product page for the M18 ergonomic chair Source for Sihoo M18 Ergonomic Office Chair with Headrest, Black
- Steelcase Series 1 user guide (maker PDF supplied on the listing) Source for Steelcase Series 1 Task Chair, Licorice, Carpet Casters
- Steelcase product page for Steelcase Series 1 Source for Steelcase Series 1 Task Chair, Licorice, Carpet Casters
- Steelcase Limited Lifetime Warranty for Americas, updated 16 June 2026 Source for Steelcase Series 1 Task Chair, Licorice, Carpet Casters
- Steelcase warranty index page listing the Americas and consumer warranties Source for Steelcase Series 1 Task Chair, Licorice, Carpet Casters
Primary sources checked .