HERCULES series folding walker with adjustable height.

Made according to the dimensions and photos from the manufacturer's website:
https://www.ebay.com/itm/356260165613 

Dimensions of walkers without wheels:
Length 53 cm (20.8 in)
Width 48 cm (18.8 in)
Height 89 cm (35.0 in)

Dimensions of walkers with wheels:
Length 56 cm (22.0 in)
Width 48 cm (18.8 in)
Height 89 cm (35.0 in)

There are 2 copies of the model saved in the scene, each with its own configured material assigned.

All objects have normal names.
All materials have convenient names.
All textures have a unique name with the model of this chair.

Weight of the walker model without wheels (Turbosmooth = 0):
51,362 polygons
52,264 vertices

Weight of the walker model with wheels (Turbosmooth = 0):
67,390 polygons
68,778 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 no lower than 1.5, since the glossiness of materials is configured taking into account PBR.