The following are the dimensions for the Controller and GK pickup of the GK-3:
Controller
| Width | 87.0 mm | 3-7/16 inches |
| Depth | 73.6 mm | 2-15/16 inches |
| Height | 22.7 mm | 0-15/16 inches |
| Weight | 0.1 kg | 0 lbs. 3 oz. |
Pickup
| Width | 102.3 mm | 4-1/16 inches |
| Depth | 7.8 mm | 0-5/16 inches |
| Height | 8.6 mm | 0-3/8 inches |
Owner's Manual: https://www.roland.com/global/support/by_product/gk-3/owners_manuals/
In the interest of product improvement, the specifications and/or appearance of this unit are subject to change without prior notice.