Specifications of the rear hub: 

Brand: BQ
Model: BQ-RH30005
Color: Black
Number of spoke holes: 36GTS
Type of brake: Disc (6 bolts)
Number of gears: HG Body 35 MM = suitable for old type Race (max 10 speed) and all MTB cassettes.
Freewheel system:    Ratchet (36T)
Points of engagement:    26
Type of axle: Thru axle Ø 12 MM
Axle included: No
Type of bearings: Industrial bearings
Average weight (GR): 323
Intended use: MTB
 
Data for spoke length calculations using the Sapim spoke size calculator: 
Total length of the hub (MM): 148
Non-gear side (MM): 35
Gear side (MM): 49
Hub diameter non-gear side (MM): 58
Hub diameter gear side (MM): 58
 
Link to spoke calculator: www.sapim.be/spoke-calculator