Hi Jennie,
Not sure why you're pen doesn't have written on it what it is, so I'm a little confused by the question.
If you've been given a pen in the UK for Lantus, it may be a Sanofi Aventis Optipen Pro 1 or Pro 2. Bluelake - not sure about Opticlick in the US, but in the UK the Optipens come in 4 colours. Yellow, blue, a kind of green and a forth colour that escapes me. But I suspect red...
Or it could be an Owen Mumford Autopen
AutopenĀ® - Owen Mumford Products - Owen Mumford Ltd.
I'm guessing it's the Optipen as you said digital and it does have a little digital display on it. You can use the snap on needles, but I happily use the BD penfine needles and they work fine. If your Optipen is getting on a bit, get another as some of the early ones had a fault. If you google for Optipen you'll see it. I tried to post the link here but it wouldn't let me
IMO, Sanofi make some fantastic insulins. If they made a pen that was as good then I'd be a very happy bunny. The Optipen I have is an obstenate beast that makes me shudder when I change a cartridge due to the jams that occur. And I really don't like the Owen Mumford ones.
Gary