First truly functional version.

Laser cut from food-safe 3mm POM plastic, filler rod wrapped around the extensions for hinge and locks.

Feedback:

• It does work
• The 3mm x 3mm POM is definitely robust enough
• The hinge / lock system is not very good yet
• Squishes the teats, water doesn't get to wash between the holder and the teat
• It is a bit large