Design IDs vs. Element IDs
LDraw Part Number are base on the LEGO Design IDs. The numbers listed next to parts at the back of LEGO instruction manuals are not the part numbers LDraw.org uses as its nomenclatura, but the LEGO Element IDs or Item IDs. A number that signifies both the part shape and color. Since LDraw parts can be any color, LDraw does not use Element IDs but solely Design IDs. In a Brick 1x2 this is typically "3004" while a Tan Brick's 1x2 Element ID is "4109995".
LDraw Part Number are base on the LEGO Design IDs. The numbers listed next to parts at the back of LEGO instruction manuals are not the part numbers LDraw.org uses as its nomenclatura, but the LEGO Element IDs or Item IDs. A number that signifies both the part shape and color. Since LDraw parts can be any color, LDraw does not use Element IDs but solely Design IDs. In a Brick 1x2 this is typically "3004" while a Tan Brick's 1x2 Element ID is "4109995".
LEGO ergo sum