The base plate is from ABS and the foam is sturdy and nice to sit on. As you can see, this is an extra wide variant. 

The width of this seat makes it ideal for your K100 or Goldwing. 

Specifications:

• Sturdy plastic base
• Covered in artificial leather
• Dimensions at the narrowest point: approx. 170 mm
• Dimensions at the widest point: approx. 250 mm
• Length: 600 mm
• Colour = Black
• Dimensions: see pictures