I am on a pump now but I got a batch of these last year when I was on MDI. I can't remember the brand name but apparently they are capless to stop you using them more than once. They are actually supposed to be like this I believe. Bloody ridiculous idea if you ask me because you either have to carry a sharps bin around with you all day, store exposed needles somewhere on your person or re use them again when they have been exposed. I would check these with the pharmacy but don't be surprised if these are correct to be like this.