Unable to identify ID in table /RPM/ITEM_D

Hi Experts,

Could you please help me in identifying alpha-numeric ID numbers in given screen shot of table /RPM/ITEM_D:

Actually, the numerical numbering (1-107851) is the one we are using for creating PPM items

I am confused to see these alphanumeric characters in ID column.

Could you please help me in identifying them.

Best regards

Saurabh