Backrest

The chair's backrest appears capable of easily catering to large users because it is 87 cm (34.25") tall, 53 cm (20.86") wide at the shoulder level, and 56 cm (22.05") wide at the pelvis area. At 128–140 cm (50.39-55.11") high, it is tall enough to accommodate any user. Contoured edges around the entire backrest aim to keep the user in an upright position, as it is the right posture for longer sitting sessions. The contoured edges also add to the sporty aesthetics of the chair. The PU pleather covering the steel frame is velvety smooth, and its pattern tries to imitate real leather. The ascending stripes and chair's other stitching are in an inferno red to further boost the chair's gaming looks. The upper part of the backrest uses lots of foam, so it can be used without the neck-support cushion.


The cut-out at the top of the headrest is something we have only come across in Nitro chairs so far. These plastic openings are for the elastic bands that secure the neck and lumbar-support cushions to the rear of the chair.


The company's name and logo appear on the backrest. On the front, the company name is embroidered in two stitching colors; white and gunmetal gray. The flame logo is in inferno red. On the plastic cut out, the company name is engraved both into the front and rear. The rear only has the inferno red flame logo.


This huge embroidered flame logo looks impressive with all the cushions removed. It is decorated with inferno red threading, which goes well with the chair's overall look.

Seat Base

The seat can also accommodate large gamers. It is 47 cm (18.50") wide and 47 cm (18.50") deep.


Like the backrest, the seat's base has contoured edges alongside stripes that ascend to meet those on the backrest. The seat's base is black, while the two stripes which adorn it are inferno red. The colored lines and stitching in the same color make for a unified appearance.

The chair's cold foam upholstery is one of the softest I have encountered. It has lots of volume, enough to keep a large user comfortably seated for even longer gaming sessions. However, whether the seat's base will keep its shape as time goes on remains to be seen. We need to use a chair for several months to ascertain whether its mold will keep its original shape. There is no company name or logo on the seat's base. Finally, Nitro Concepts states that the PU cover is breathable because of a unique, built-in system, but there are no visible pores.


Should you want to relax a bit while gaming or working, a lever on the right side of the seat's base can adjust the backrest's tilt from 90 to 135 °.


By pushing it inward or pulling it outward, you can lock the tilt in place or set it free. Additionally, lifting or pushing down the lever adjusts the height of the chair, which varies from 128 to 140 cm (50.39–55.11").


The chair comes with a rocking mechanism with up to a 14° angle, and its tension can be adjusted via a knob that turns clockwise under the seat's base. Under the seat's base, we also find two metal bars which reinforce the steel frame and the class-4 gas lift, which is responsible for the chair's height adjustments. The gas lift is capable of lifting a maximum load of up to 300 lbs, which is not mentioned by the manufacturer.


The right side of the seat's base has a slight fault on the cover under the armrest. This is probably a manufacturing error and hopefully only a one-off with our sample. Nonetheless, it is pretty easy to fix this. You just have to loosen the screws that hold the armrest in place, move it a bit further from the seat base, and everything will be fine.

Armrests

The S300 EX comes with 3D armrests, which can easily be adjusted from left to right and in height and angle. Each armrest only has one button for height adjustments. They are made out of soft rubber to keep the armrests stable while seated, and the armrests are 25.5 cm (10.04") deep and 9.5 cm (3.74") wide, which is pretty slim compared to other chairs we have evaluated so far.

Neck and Lumbar Support Cushions

The S300 EX comes with two complimentary cushions made out of fabric and not covered in PU pleather as the rest of the chair for extra support; both are also easily removable. The neck-support cushion is soft and the smaller of the two; it has the logo of the company (flame) in inferno red threading. The larger neck-support cushion has the company name embroidered in white and gunmetal gray. It also has a small flame logo in red stitching.


Both cushions have straps that run down the rear of the backrest.

Gas Lift, Five – Star Base And Casters

The five-star base is made out of plastic (nylon), while its five arms have inferno red highlights. Altogether, we have a unified color scheme. While quite light, the base appears durable enough to hold the 135 kg (297.62 lb). Instead of the 60 mm caster wheels, which most companies tend to use, the S300 EX comes with 50 mm caster wheels made out of a hard nylon core coated in soft polyurethane. The wheels roll across flat surfaces smoothly and quietly.

Accessories

In case the two complementary cushions somehow are damaged, a memory foam pillow set is available for €49.90 on the official website. However, the filling of these cushions differs from those included with the chair.