alb - First number is track armor. Second is hull armor plus track armor. Possible to have both track and hull penetrated. Dice for damage one time.
s40 = Spaced armor bases - Armor value vs HEAT/HESH rounds.
28 = High slope indicator vs APDSX / HVAP rounds, i.e. deflection. Add +1 to the variable penetration die.
c = Low profile cupola - only 10 backed by another 10 scores a hit.