The Brass Kaleidoscope is 7-1/2". Just rotate or shake gently and a whole new beautiful array will suddenly appear. The "T"-Style Kaleidoscope is 9" long and produces beautiful patterns on its own, but really excels (awesomely) when you insert the transparent 10 long color filled tube through the head (as shown). Moving the insert back and forth and tipping it produces an almost psychedelic experience. While we've seen lots of kaleidoscopes in our time, they've not been like these two. What gems. Whichever one you choose will be a great hit. The two alternative images show two of the innumerable spectacular patterns that you will see. Great fun will be had by all.