Boat Propeller

These are 50mm Diameter Propellers I made for my 3d Printed Tug Boat. I Don't know the Pitch of the Prop as I don't know how to calculate them. It is designed for a 5mm shaft and has a 5mm nut slot on it for ease installation.
https://www.youtube.com/watch?v=oz8k-SL4xmU
https://www.youtube.com/watch?v=VgSK_t1zPG4&t=49s
I have added some designs.
Update as of April 17, 2018
Added two propellers 40mm diameter for 3mm shaft. One is 3 blades and the other 4 blades. Both have approx. 16mm pitch. These 40mm props are for the Stan tug 1004
https://www.youtube.com/watch?v=E_U5nFjZ52Q
https://www.youtube.com/watch?v=aPyz4pVPPgE

Update:
Added the prop duct and rudder blade.

If you like the design and find it useful, a little tip is highly appreciated. It will go a long way in my continued design developments and testing for all my design works. Thank you very much!!