When looking at the ULTRASTICK™ PHASE-CHANGE material from Aavid, you may see different part numbers on the material body.
The datasheet indicates the part number “100300F00000G ”:
However, you may receive the actual product with the part number “031117 ”:
Aavid has confirmed that both are the same part. This is the Aavid internal item number and they just listed their internal part number on the product.