This 12" wood shelf is 12" long and made of 8" wood, so it measures approximtely 12" x 7.5". Good size for a chinchilla to have some fun on! 
Would you like a hole in your shelf? Be sure to select that listing as well and add it to your cart!
Picture coming soon... bolts can be installed however you want -- long side, short side, one long & one short, and so on...

 
Which side do you want the bolts on? Short side? Long side? Both? Custom?