The model is made according to the manufacturer's dimensions and photos:
https://www.bizchair.com/products/commercial-wishbone-style-wood-and-kraft-paper-stack-dining-chair-zh-8101ys 

The scene contains 2 copies of the model, each with its own material.
The models have a Turbosmooth modifier assigned with Render Iterations=1 mode, which is applied only during rendering.
The obj file contains a model without Turbosmooth to save file size.

Dimensions:
height 44.6 cm (17.5 in)
width 54.5 cm (21.4 in)
depth 55.3 cm (21.7 in)

All objects have normal names.
All materials have convenient names.

Model weight: 626,384 polygons, 626,782 vertices

Pivot Point is aligned to the center of the model.

Those who work in V-Ray version lower than 3.1, be careful, in the materials in the BRDF section there is Microfaset GTR (GGX), if your version is older than 3.1, then the BRDF field will be empty. Select Blinn, Phong or Ward - what is preferable for you.

For Corona render, it is recommended to install version not lower than 1.5, since the glossiness of materials is configured taking into account PBR.