Please fill out the form below for Stiffener Aft Cowling and get a quote for part number D311-8 by Robinson Helicopter, 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 D311-8. ASAP Aerospace distributes nose to tail NSN components, sub-assemblies, and assemblies for the aerospace and aviation industry.