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OFFISTOCK - office . furniture . sorted
OFFISTOCK - office . furniture . sorted

Our jargon-busting guide to the chair-nical terms...


Styled and designed to deliver a more luxurious look and feel, generally less functionality than a task and operator chair.


Task & Operator

Practical and multi-functional that caters for a wide variety of users.


A product with specific ergonomic qualities normally has a higher level of adjustment and functionality than any other category.


Heavy Duty

Product with a weight rating that exceeds 150kg or 23 stone.

Conference & Visitor

Often supplied in either 4 legged or cantilever frame variants these products are often used in boardrooms, side chairs, or similar applications.



This category encompasses ‘tub chairs’, ‘modular seating’ and ‘booth’ type seating.


Chairs that are practical and stylish to compliment all waiting areas. This category encompasses ‘tub chairs’, ‘modular seating’ and ‘booth’ type seating.


The mechanism is often the most expensive and complex part of an office chair.
The mechanism determines the angle and height of the seat and back move in relation to one another.

‘PCB’ Permanent Contact Back

Single lever has height adjustment only, ‘PCB’ / 2 lever adjusts back rake only, seat pan remains in a horizontal position.


Lock / Tilt Motion

Although the angle of the seat and back rake is adjustable their angle is fixed in relation to one another. On a single lever variant, the recline on this product can only be ‘locked off’ in an upright position. Twin lever can be ‘locked off’ in any reclined position.

Knee Tilt (sometimes known as ‘swan neck’)

Angle of seat and back remain the same as with ‘lock tilt’ mech, but the product is hinged lower and nearer the front.


Synchronised Tilt Mechanism

Back rake and seat tilt move in relation to one another (generally 2:1 i.e. 2 degrees of back rake to 1 degree of seat tilt) This action means that instead of the body of the user remaining at a 90” degree angle, the body is extended/straightened when reclined in free float. Twin lever product can be ‘locked off’ in various reclined positions, single lever can only ‘locked off’ in an upright position.

A-synchro / Autonomous Synchronous

The ‘back rake’ and ‘seat tilt’ can be adjusted completely independently of one another. Often this ‘Mech’ type has ‘forward tilt’ / ‘pelvic tilt’ function. This is more popular with a user that prefers a more upright/forward seated position.



Auto Tilt Tensioner

The tension control affects the amount of pressure required to recline the back rake and/or seat tilt. This then caters for a lighter or heavier user and means the resistance can be made ‘weaker’ of ‘stronger’ accordingly. Auto-tension product will automatically adjust to the weight of the user.


Anti Kick

This is a safety feature which means when the tension control of a product is adjusted to cater for a heavier user and the product is locked off into a reclined position, the product will need the same level of force applied to release the recline lock, prior to the product returning to an upright position, preventing potential injury for a lighter user.

Seat Slide

Seat slide allows the user to adjust the seat depth to the optimum position. Seat slide comes either as standard on certain products, or can be fitted retrospectively to certain products.


Adjustable Backs

Just as with a seat slide height adjustable back, this caters for both ‘taller’ and ‘shorter’ users and with different supportive requirement.


A good quality lumbar should have an element of adjustment. Adjustment can incorporate either lumbar prominence, height, or shape.


Fixed / Kidney

This is in the form of 2 x bolsters positioned on the left and right on the back support either side of the lower part of the spine.


Operated through either cable or thread which can adjust either prominence or height.



Inflatable bag sewn into the back effects prominence.


Offers height adjustment but not prominence.


Floating Lumbar

Back support is split and automatically self-tensions to the shape of the user.

Gas Height Adjustment

Adjust the chair height as desired.


Adjustable Arm Rest

Fully adjustable, multi-positional armrest; height, width and depth movement caters to users of all shapes and sizes.


Relieve strain by providing support for the forearms.


Height Adjustable Arm Rests

Adjust armrest height to suit individual requirements.

Seat Angle Adjustable

Lever adjusts seat angle to encourage recommended seat position.


Adjustable Headrest

Adjustable headrest for optimum support and comfort.

Adjustable / Free float back

Optimal comfort by locking the backrest at any angle or a free float option.


Independent Seat & Back

Position seat and back angle independently for optimum support and posture.

Folding Arm Rest

Stylish, comfortable, and functional folding arm provides optional support.


Tilt Tension Adjustment

Adjust the tension of the seat tilt mechanism to support individual requirements.

Infinite Lock Mechanism

Lever adjusts seats and back angle as one lockable in any position.


Seat Depth Adjustment

Adjust the backrest depth for a larger seating area, suited for longer or shorter legs.

Anti Shock

Prevents user being thrown forward when adjusting angles.



Provides support and relief for the head and neck muscles.


There is a variety of different castor sizes and types.

Brake loaded

When seated on product, castors change from fixed to free wheel.

Brake Release

When seated on product castors change from free wheel to fixed.

Soft Wheel Castors

Nylon compound on wheel surface. Used on more delicate flooring types to reduce potential damage.


Used for applications where a fixed seating position is required.


Casing or side wall of wheel can be supplied chromed.



Standard pistons are available in a variety of different lengths and shape. The lower section of the piston which fits into the base is a tapered cone shape, the angle and shape of the taper effects how deep the piston sits in the base and can additionally determine the height range of the product.

Fixed Height

More popular in boardroom applications where continuity in height is required.

Memory Return

More popular in boardroom application this piston will return the seat to a forward facing position. This piston type has no height adjustment.


This piston allows electric current to pass through the product and be grounded. Popular where sensitive electronics are present.

Draftsman Kit

Draftsman kit consists of: Elongated gas stem with gator, foot ring and glides. Used in application where an elevated height is required. Please note, increased height range differs slightly depending on product. Not recommended for seat tilt applications.


Fabrics & Foams

Standard Foam

Cut to shape from a roll of ‘sheet foam’ then tension from fabric over base of product creates shape. 

CMHR (Combustion Modified High Resilient) Foam

This is used when the strictest fire code standards are required, such as in hotel lobbies, hospitals, schools, mass transit (airplanes, buses). The foam has a high density which helps it last a long time. Fire retardant chemicals in the foam give the texture a grainy feel.


Poured / Cured Foam

Hot liquid injected with a large quantity of tiny air bubbles, then poured into a mould and set. Higher density means firmer than ‘sheet foam’, but has greater longevity. Moulded foam is more versatile in shape and does not require tension from fabric to retain the shape once produced.


Helps buyers identify products and materials that have low chemical emissions, improving the quality of the air in which the products are used. All certified products must meet stringent emissions standards based on established chemical exposure criteria. Certain seating products carry testing.


Wooden Product

The FSC allows consumers to identify, purchase and use wood, paper and other forest products produced from well-managed forests and/or recycled materials. Although Offistock is not FSC accredited, Impulse and Evolve product use board from a manufacturing facility that holds FSC accreditation.

Find out more



Faux leather finish with hard wearing factors and an exceptional soft touch appeal. Easy to clean and have a 30% cotton content for a natural feel.


A richly textured hard wearing fabric with the look and feel of wool. Treated with super stain guard finish that helps protect against stains and spills. 

Request your free sample


Stylish clean cut fabric from Yorkshire mill, Camira. Extensively used in domestic and contract applications

Request your free sample

Bonded Leather / Enviro-leather

Genuine leather cuttings from factories and tanneries are recycled to manufacture an environmentally friendly material. It is manufactured with specific properties which make it look, feel and even smell like leather. It is more durable and hardwearing than genuine leather.  a polyurethane coating is applied to give a soft feel and rich colour.

Bonded leather is produced in a similar process to paper manufacturing. Leather cuttings are dispersed in water and are shredded and milled by special grinders to free the leather fibres. Mixing these fibres with natural latex binders and other additives, a leather fibre pulp is produced. The pulp is then continuously poured and processed on a web, which is then dried and reduced to a uniform thickness. The surface is then embossed with a grain to make it look like natural leather and finally a polyurethane coating is applied to give a soft feel and rich colour.


Casing or side wall of wheel can be supplied chromed.


There are many bespoke testing standards covering various aspects of products. Attained certification varies from product to product depending on application. The most popular of these are as follows:

BS5852 Test 0 & 1

British Standard match and fire retardancy standards. All Offistock product carries this certification in every instance.



Additional fire retardancy certification is sometimes required for product that is being supplied into an environment where there is an increased risk of death through fire i.e. sleeping quarters. Although not required for the majority of end user applications, it can be stipulated within a product brief. Many products already carry this additional certification or can be made to this specification. The term ‘crib’ is taken from the test to ensures consistent conditions and standard. 


This test deems certifies that a product is suitable for an environment that can be used continually for a 24 hour period.



This test covers various aspects of the structural and stability elements of the product to include weight testing to 150kg, tipping points, trap points.

DSE’ Compliance

In the interest of health and wellbeing of all employees. The Health and Safety Executive (HSE) has made recommendation that furniture and seating should meet certain criteria and a level of specification for compliance. This is covered under the "DSE" Work Assessment (Display Screen Equipment) guidelines.