Please fill out the form below for Box Assy Oxygen and get a quote for part number B431561-503 by Bombardier Aerospace, please include required quantity along with expected turn around time. Our knowledgeable account manager will reply you shortly. Also check for the related parts for part number B431561-503. ASAP Aerospace distributes nose to tail NSN components, sub-assemblies, and assemblies for the aerospace and aviation industry.