I know there is a lot of customization available for the Nomad, but does it have to have a sleeve? I favor the subtle muted looks of the wood, which I think allows the architectural aesthetics to take center stage. The sleeves are great, but I find they kind of hide the artistic craftsmanship of Dan's creative design. Personally, being half Japanese, I find the extreme attention to detail of every aspect of this vaporizer makes it so special. I believe when the lines of this vaporizer are emphasized, it really shows the amount of creativity and craftsmanship Dan has put into his work. Sorry I got carried away, so back to the question, does it have to have the sleeve?