Passing Multiple Value In Single Parameter

How do I pass the multiple value in the single parameter? Here is the select simple select statement with two fields (ID and Map_Area):

SELECT *
FROM TestParamOne

Here is the output:

ID Map_Are
12345KK45
657463IIY7
34345FGD
44342DFRE
4646DSAW
424245DSAW
12121DSAW
5753FRDE
575737FRDE
1121FRDE
1121F5FR
646462F5FR
8568F5FR

Here is my simple stored proc. Right know I only can execute with one value at the time but I am trying to run the stored proc with more than one value.

CREATE PROCEDURE TestParam1
@Map varchar(4)
AS
BEGIN
SET NOCOUNT ON;

SELECT ID, Map_Area
FROM TestParamOne
WHERE Map_Area=@Map
END
GO