This specification covers flexible couplings for joining tubing with AS5131 Type A beaded ends for use in aircraft fuel and vent systems (see 6.1) Classification Couplings shall be of the following size@ material@ and type as specified Size: The size of couplings shall be as specified in Table 2 Material: The material shall be in accordance with Table 1. The basic material of the coupling is designated by the following code letters CODE D - Aluminum CODE C - Corrosion-resistant steel CODE T - Titanium Type: The coupling shall consist of the following types Type 1 - Standard coupling with no electrical bonding Type 2 - Coupling with electrical bonding