We are saving used hardback books that did not sell the second time around and are making them last longer! This is an actual book (comes in assorted titles) was converted to hide a tin container, which is also included with the hollow book safe. Hollowed out rectangular space can also comfortably hold most smartphones (5.5 in x 3.7 in x .9 in). The outside and inside dimensions of the book are variable. Please contact us directly if exact dimensions are needed. The book you receive was actually saved from being shredded. We make these treasured hardback books last LONGER! It is the philosophy of Greenfire to create eco-friendly products that serve more than just one purpose; this product is an example of that. Thank you in advance for supporting an all natural and sustainable business.