This is the iconic Kerbal Space Program rocket brought to life through 3D printing.
If you'd like to play with this rocket in KSP you can download it here.
Measurements are in millimeters:
Small - 75.5 x 20.5 x 17.7
Regular - 100.7 x 27.3 x 23.6
Large - 200.0 x 51.9 x 45.5
Photos show regular size