My Select Case is not returning the correct string. For example, when L =
39, my code always returns "18'' T12 (F18T12HO)" and not "36'' T12
(F36T12HO)", why?

I think VBA is just looking at the first part of Case and not the part after
the AND. I'm not sure how to force it to look at the part after the AND.

Sub cmbEstimate_Click()

Select Case L = Lwidth - Sockets

Case L < 18
MsgBox "This cabinet is too small to use Fluorescents.", vbCritical
Exit Sub

Case 18 < L And L <= 24
cboLamps1 = "18'' T12 (F18T12HO)"

Case 24 < L And L <= 30
cboLamps1 = "24'' T12 (F24T12HO)"

Case 30 < L And L <= 36
cboLamps1 = "30'' T12 (F30T12HO)"

Case 36 < L And L <= 42
cboLamps1 = "36'' T12 (F36T12HO)"

End select

End sub

Thanks in Advance,
Ryan