This is a Cannon for vehicle mode of Transformers Combiner Wars Stunticon Brake-Neck ( also known as Wildrider). This is inspired by the G1 accessories for Brake-Neck. The print has multiple 5mm ports for multiple combination and play options. It also has built in foot pegs and slots for Titan Master and Prime Master figures to stand on or sit on. Cannon Barrels have 5mm ports for Seige Blast Effects
You will need the Stunticon Car Cannon Adapter to use this in vehicle mode and robot mode
https://www.shapeways.com/product/45X5EFXQ9/car-cannon-adapter-for-tf-cw-stunticon
This can be attached to other Transformers using Adapters
5mm circle port to 5mm peg adapters:
https://www.shapeways.com/product/8AHZAPH69/tf-5mm-circle-port-to-circle-peg-adapter?optionId=146734905&li=shop-inventory
5mm hex port to 5mm peg adapters:
https://www.shapeways.com/product/592FMF6MF/tf-5mm-hex-port-to-circle-peg-adapter?optionId=146747621&li=shop-inventory
This is intended for adult figure collectors. This is not designed for rough play by children.
This was tested with White Natural Versatile Plastic and fit with no problems. Depending on the plastic you choose, sanding or polish may be needed to fine tune the fit.