106mm Recoilless M93 Case

[Antman]

I have two empty cases for the 106mm Recoilless with the base plug for the M344A1 projectile. Case 1 is a brass platted steel case.
Case 2 is a brown lacquered steel case. In addition, case 2 has a 3" (76mm) Red Band at the case mouth and a 2 1/2" (63.5mm) Yellow Band at the base of the case. What do these bands signify?

 

[HAZORD]

Never heard of a brass plated 106RR case. Photos?

 

[Antman]

Hazord--Sorry, no way to take a picture. The case may not be brass plated, but is brass colored and is steel. Appears to be a factory finish. Could be anodized but does not have the right look for that. The headstamp is "106MM M93B1 S1W 20-25 1956"