Rim Specifications:
Brand: Rigida - Ryde
Model: Zac 421
Color: Black
Size (Inch/MM): 28" / 622
External width (MM): 26,5
Internal width (MM): 21
Weight (GR): 640
Material: Aluminium
Single-walled / Double-walled: Double-walled  disc
Number of spoke holes: 32
Spoke nipple size: 14
Brake surface present: no (disc)

Data for spoke length calculations using the Sapim spoke size calculator:

Internal diameter of the rim (MM *Not ERD*): 590

Rim thickness (MM): 2

Number of spokes in the wheel: 32

Number of crossings gear side: of your choice

Number of crossing non-gear side: of your choice

Link to spoke calculator: www.sapim.be/spoke-calculator