Metal spiral stairs for modern house exterior design

Metal spiral stairs for modern house exterior design
Description
Metal spiral stairs for modern house exterior design

Specification: 
Center post 76*4mm in carbon steel
Stringer 114*4mm in carbon steel
Tread 6mm thickness tread in carbon steel
Railing # height 36''/42''/1000mm
Vertical tube 25mm in carbon steel
Top handrail 42mm in carbon steel

Stair tread options reference and can be customized as well: