Contact dealer. **Includes 48" high load backrest. Series WB Technical Information Series WB Technical Information Model 20WB: 2000 lb at 24" load center. Model 30WB: 3000 lb at 24" load center. Model 40WB: 4000 lb at 24" load center. Maximum Battery Size 31.75" wide x 13.12" long x 23.25" high. Batteries Up to 600 amp hour capacity available. 24 volt electrical system. The 20WB, 30WB, and 40WB must have a battery weighing 975 lbs or more. Travel Speeds In third speed: Loaded, 2.5 mph; Empty, 3.