GALFAN is a zinc-aluminum alloy, Zn-5Al-MM, UNS Z38510 in ASTM designation. It consists of 5% aluminum and 95% zinc alloy.
The following table lists the chemical requirements of this alloy, according to ASTM B750.
| Element | Composition, % |
| Aluminum | 4.2-6.2 |
| Cerium+Lanthanum, total | 0.03-0.10 |
| Iron, max | 0.075 |
| Silicon, max | 0.015 |
| Lead, max | 0.005 |
| Cadmium, max | 0.005 |
| Tin, max | 0.002 |
| Others, each, max | 0.02 |
| Others, total, max | 0.04 |
| Zinc | Remainder |