Rim Specifications:    
Brand:    Rigida - Ryde
Model:    Andra 40
Color:    Silver
Size (Inch/MM):    507X25C
External width (MM):    30
Internal width (MM):    25
Average weight (GR):    625
Material:    Aluminium
Single-walled / Double-walled:    Double-walled
Single eyelets / Double eyelets:    No eyelets
Number of spoke holes:    36GTS
Spoke nipple size:    13G
Brake surface present:    Yes
    
Data for spoke length calculations using the Sapim spoke size calculator:    
Internal diameter of the rim (MM *Not ERD*):    477
Rim thickness (MM):    3
Number of spokes in the wheel:    36
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