Need help with simplifying this statement using IF, OR & LEFT or finding a better way!

This is my first post and I'm hoping that someone can help me out. I've been searching around for a solution and the one I've managed to cobble together just doesn't seem efficient at all and seems to hog resources.

I have a column of various part numbers with different 3-digit prefixes which designate their type (Finished Good, Sub-Assembly, Raw Material, Supply Item). For example, the prefixes 100, 200 & 300 indicate "Finished Goods", so I would want a formula to look at column A and return "Finished Goods" into Column B for any parts with those prefixes. The same also applies for other prefixes and part types.

I was able to accomplish this with the following formula, but it's gigantic and would have to be much larger in order to include all of the prefixes that exist (approximately 35 different ones):

=IF(OR(--LEFT(A7,3)=100,--LEFT(A7,3)=200,--LEFT(A7,3)=300),"Finished Good", IF(OR(--LEFT(A7,3)=150,--LEFT(A7,3)=155,--LEFT(A7,3)=250),"Sub-Assembly", IF(OR(--LEFT(A7,3)=180,--LEFT(A7,3)=280,--LEFT(A7,3)=350),"Raw Material", "Not Found")))

There has got to be a better and more elegant way to do this, I just haven't been able to figure it out.

Any help is greatly appreciated!

Below is an example of the end result I'm looking for.

Column A	Column B
100-001001	Finished Good
200-001001	Finished Good
300-001001	Finished Good
150-001001	Sub Assembly
155-001001	Sub-Assembly
250-001001	Sub-Assembly
180-001001	Raw Material
280-001001	Raw Material
350-001001	Raw Material
700-001001	Supply Item
710-001001	Supply Item
730-001001	Supply Item

Originally Posted by RobertMika

=IF(OR(--LEFT(A7,3)={100,200,300}),"Finished Good", IF(OR(--LEFT(A7,3)={150,155,250}),"Sub-Assembly", IF(OR(--LEFT(A7,3)={180,280,350}),"Raw Material", "Not Found")))

Or probably VLOOKUP woudl be better.
make a table within your workbook and use
=VLOOKUP(--LEFT(A2,3),$K$2:$L$50,2,0)

Where $K$2:$L$50 is the table to look at.

Thanks for the tips. I wanted to avoid adding additional tabs to the workbook and doing vlooks, so your code works just fine. I had tried something similar but I guess I wasn't getting the formatting right. Thanks a bunch!