Where is the oyster card reader at finsbury park tube?

It’s a while since I’ve been to Fin Park but I have a feelng it’s on the platform itself.

What is an oyster card?

@Darwin it’s the name of the payment card for London transport. It works by “loading” a ticket or money on to the card at the ticket office (or online) and you use it by passing close to readers as you get on and off the tube or buses etc. You don’t have to take it out of your bag, just have to get it close

But why oyster? I keep thinking of carpenters and walruses.

“The time has come,” the Walrus said,
“To talk of many things:
Of shoes—and ships—and sealing-wax—
Of cabbages—and kings—
And why the sea is boiling hot—
And whether pigs have wings.

”“O Oysters,” said the Carpenter,
“You’ve had a pleasant run!
Shall we be trotting home again?’
But answer came there none—
And this was scarcely odd, because
They’d eaten every one.”