There is one sealing ring that helps to prevent air leak at the elbow joint. (See pic). It's made out of pretty hard plastic and mine is already broken. I could not find any replacement parts as they only sell the entire motorhead for 80ish dollars.
This is designed to fit V7. But may work with other models. Here is the info for the part if you look that up for reference. Dyson Motorhead, Quick Release Assembly SV11 #DY-968266-04
Material: Saintsmart TPU.
Nozzle: 0.4mm
Layer Height: 0.2mm
This is a tighter fit and I used some silicone grease to make it fit better. Print with 97%ish scale if you like for looser fit.
Comment for questions.
The author hasn't provided the model origin yet.