This is a Eurocard. It's one of many telephone calling cards I can buy here in Spain. I think you can get something similar in Tesco's.
By dialling lots of code numbers it's possible to make a phone call using, what I suspect, is voice via internet technology. I have to pay 6€ for the card and from the first time I use it I have up to 800 minutes call time from my own phone or 45 minutes from a call box and 45 days before it expires. In the call box there are no other charges but from my home phone the call also has to be paid for at the equivalent of the lo-cost call rate in the UK.
When the car was broken into, when I first got here, and I had to spend nearly 50 hours on the phone this card saved me a fortune. The best thing about it though is that it allows me to keep in touch with pals back in the UK at a reasonable cost and without all that rigmarole involved with computer based phone calls.