Speaking of competency, one important thing to consider is AS9120 certification. The AS9120 is the international standard committed to the improvement and assurance of integrity of the aerospace industry. This standard differs from the AS9100 (also a global aerospace standard); AS9120 is a standard for stockist distributors.
AS9120 certification services from certification parties like International Standards Authority are for companies selling and distributing aircraft parts and materials. The standard requires strict compliance with ISO9001, so AS9120-certified companies are also ISO9001 certified.