Micro #28

Micro #28-1 (iron sulphate and potassium hydride).
Micro #28-2 (iron sulphate and potassium hydride).
Micro #28-3 (iron sulphate and potassium hydride).
Micro #28-4 (iron sulphate).
Micro #28-5 (iron sulphate).
Micro #28-6 (iron sulphate).
Micro #28-7 (iron sulphate).
Micro #28-8 (iron sulphate).