Dr. Pen Dermaroller - The Needle Attachments?

[londonhairlossvictim]

Hey guys, I got a Dr. Pen dermaroller, it comes with 2 sets of needle attachments

I am reading mixed reviews online that says after every usage, you should use a new one

Or can they be cleaned somehow, using hot water?

Or is it better just to buy new needle attachments, and to always use a new one every time that is used, isn't that expensive?