BS EN 2923:2019 pdf free.Aerospace series - Nuts, hexagon, plain,reduced height, reduced across flats, in heat resisting steel, silver plated- Classification:600 MPa threads一Part 2: Limit dimensions for bolts and nuts ISO 8788, Aerospace一Nuts, metric一Tolerances of form and position ISO 9139, Aerospace一Nuts, plain or slotted (castellated)一Procurement specification TR 3823-002， Aerospace series 一Materials for plain, slotted and self-locking by plastic ring hexagonal...