It is not valid XML. You cannot have element named as number.

One of XML Naming Rule is: Names cannot start with a number or punctuation character

http://www.w3schools.com/xml/xml_elements.asp

But if you still want it as non-XML text, you can do the following with Dwain solution:

DECLARE @t TABLE (Part INT, Color VARCHAR(10), Size VARCHAR(10))

INSERT INTO @t

SELECT 123,'blue','small'

UNION ALL SELECT 124,'black','medium'

UNION ALL SELECT 125,'red','large'

select * from @t

DECLARE @xml VARCHAR(max)

SELECT @xml = (

SELECT Part, Color, Size, '/' + cast(Part as varchar) AS PartC

FROM @t

FOR XML PATH(''), ROOT('PartsList') )

SELECT REPLACE(REPLACE(REPLACE(REPLACE( @xml,'</Part>','>'),'<Part>','<'),'</PartC>','>'),'<PartC>','<')

Please Note, you will not be able to load above text to DOM object for use as XML...