These Castor Wheels-Set of 4 are designed for use with Smartbox SB-M10. They allow for an easy install on the Charge & Sync Smartbox SB-M10 for use as of the device a Free Standing Charge 7 Sync trolley, Up to 2 Smart boxes can be stacked on top of each other when used with castors. 

PRODUCT SPECIFICATION

* Designed for Smartbox SB-M10
* Set of 4 Castors
* Up to 2 Smartboxes can be stacked on top of each other. 

PRODUCT FEATURE

* Easy to install and use
* Saves desk space & provides Mobility
* Flexibility to easy moves the Smartbox between rooms.