Are the free ones! These are the cores of some toilet paper rolls. My son had fun using them as binoculars. This morning my other son turned an Amazon box into a truck. Kids just have such amazing imaginations because they haven't yet been constrained by the rules of the world. I love seeing life through their eyes.
Seriously! Boxes and any form of cardboard!!!! My kids play with them too (even the 12 year old will still make something out of them!) He's adorable I love his binoculars!
