Insulin Pen Needle Color Code Blue Gauge 31 Gauge HCPCS A4215 (Disclaimer) Hub Connecting Type Pen Connection Hub Material Polypropylene Length 8 mm Needle Material Surgical Steel Safety Feature Without Safety Sterility Sterile Type Regular / Short UNSPSC Code 42142523 Usage Disposable Wall Type Thin Wall Without Safety Lilly and Novo insulin pens and dosers