You are looking at 4 x arched detail girder bridge 'sides' only for model railway. Available in OO Gauge only because of the rivet detail not working with small sizes - you will receive 4 bridge sides. These will be 3d printed in grey and have the design on one side only (shades may vary).
These are not self standing but not very stable when they are but i'm sure you will be fixing these in place anyway.
Dimensions:
OO Gauge: 190mm L x 3.9mm D x 22.8mm H