Reason for rounded fitting at the top end of Allihn Condenser

![enter image description here](https://i.stack.imgur.com/GFE16.jpg)


I am purchasing an essential oil distillation setup. The Allihn Condenser at the top end, and the attached glassware, are rounded. It is supposedly 24/40. I have never seen this. If one of them broke, I would have a hard time finding a replacement because of the strange shape. Thus, I am wondering if there is a good reason for the shape, or if I should ask the manufacturer to give me a normally-shaped 24/40 connection.


Thank you for sharing your thoughts, in advance.


