They have a full pixel display. They are different. E-Ink displays are 1.18mm thick per their spec sheet and you have to add some mechanically stiff backing to that.
Looking at a detailed photo [1] it looks like a STN segmented LCD but I could be wrong.
Incidentally, do you have a pair of callipers handy? Could you measure the PayPal Security Key?
I don't think it is the same thickness as a credit card.
They have a full pixel display. They are different. E-Ink displays are 1.18mm thick per their spec sheet and you have to add some mechanically stiff backing to that.
Looking at a detailed photo [1] it looks like a STN segmented LCD but I could be wrong.
Incidentally, do you have a pair of callipers handy? Could you measure the PayPal Security Key?
I don't think it is the same thickness as a credit card.
[1] http://www.stahlke.org/dan/displaycard/front.jpg