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Trade terms for professionals and design studios
Sedus opens the se:flex brochure with a number rather than a chair: rents keep rising, and the average office is occupied for only half the time. Hybrid working answers with non-territorial desks, and a desk that belongs to no one is a chair that belongs to three or four people a week. se:flex was drawn for exactly that desk. Its Similar mechanism senses the weight of whoever sits down, between 500 and 1,500 N, and sets the backrest counter-pressure without anyone touching a knob; a slim task office chair that is ready before the laptop has booted.
The mesh version, ef-122, carries a three-dimensional knitted membrane in five colours and is the one British desk-booking floors tend to specify as a mesh office chair; ef-102 swaps it for a slim upholstered back in any Sedus fabric, with an anthracite rear whatever the front. Both share the patented flex element between seat and back, a seat that slides 70 mm (2¾ in), and the choice between multifunction and 4D armrests, the latter part of the DIN EN 1335-1:2023 Type A configuration.
Around the shared floor the family keeps going: a counter-height version with a Ø 500 mm (19⅝ in) footring for standing-height benches, a four-leg visitor chair that stacks five high, and a cantilever chair for the meeting room, all with the same two backs. On a plan with more people than desks, La Mercanti writes the desk-to-chair ratio before the chair codes.
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It sits on a longer gas lift and an aluminium base, with a Ø 500 mm (19⅝ in) footring adjustable between 300 and 500 mm (11¾-19¾ in) and a seat height of 630-880 mm (24¾-34⅝ in). The seat depth is fixed at 425 mm (16¾ in), the castors brake when the chair is unloaded so it does not roll away as you stand, and Sedus recommends it for users up to 110 kg (243 lb).
A compressive load between 500 and 1,500 N, which Sedus translates as roughly 10 N per kilogram, so from about 50 kg (110 lb) to 150 kg (331 lb) of sitter. Within that span the backrest tension follows the person. The chair itself is recommended up to 130 kg (287 lb) on the polyamide base and 150 kg (331 lb) on the aluminium one.
Yes, as an option. The ef-220 frame takes castors of Ø 37 mm (1½ in) in place of the glides, and Sedus states that it still stacks five high on a flat surface. Standard glides are stainless steel, with plastic or felt versions for soft and hard floors; the cantilever ef-230 takes plastic or felt glides only.
Any fabric in the Sedus collections, arranged in price groups: polyester weaves such as Atlantic, Era, Nova, One, Phoenix and Tempt; recycled polyester Cura and Cyber; wool blends Fame, Umber, Remix and Steelcut Trio 3; imitation leather; and Scala leather. Abrasion resistance ranges from 50,000 to 200,000 Martindale cycles across the range, and the rear of the back stays anthracite whatever the front.
Sedus declares the Blauer Engel award on the se:flex product page, alongside the GS mark, the TÜV Ergonomics and harmful-substances certificates, GREENGUARD, Quality Office and the AGR seal. The 2026 price list lists the same set without the Blue Angel, so for a tender La Mercanti asks Sedus for the current label document rather than quoting from memory.
A se:flex leaves the factory with castors for one type of floor. After a move or a new carpet, five steps put the right set under the chair without tools.
Sedus marks se:flex castors as type H, hard tread for soft flooring, or type W, soft tread for hard flooring. The letter on the castor tells you which set the chair has now.
Carpet tiles want the hard H castor; timber, stone and resin want the soft W one. A desk-sharing floor with both surfaces gets the castor of the surface under the chair, not the one at the door.
With the se:flex on its side, each castor pulls straight out of the base and the new one pushes in until it seats. No tool is involved; the instructions for use say exactly that.
New castors arrive with a coloured protective cap. It comes off before the chair is used, otherwise the first roll leaves marks on the floor.
The counter-height se:flex uses constantly braked castors that only free themselves under load: they are not interchangeable with H or W and stay with that chair.
