LEGO is trying to make its iconic toy bricks more sustainable.

The Danish toymaker unveiled a prototype brick made entirely from recycled plastic. LEGO says the plastic comes from discarded bottles.

A one-liter plastic bottle provides enough raw material for ten 2 x 4 LEGO bricks.

LEGO says more research is needed BEFORE the bricks can hit the store shelves. The next phase of testing is expected to take at least a year.