sql – Error on converting data type nvarchar to numeric


So i have this table in MS SQL:

create table MobileUnit(
IDMobileUnit int identity  primary key,
Type numeric null,
Length numeric null,
Width numeric null,
Height numeric null
);

My task is to insert xml data into this table, and i have done this:

<MobileUnit>
            <Type  />
            <Length  />
            <Width  />
            <Height  />
          </MobileUnit>
    INSERT INTO MobileUnit(Type,Length,Width,Height)
        SELECT 
        Type=c.value('Type(1)','numeric(18,0)') ,
        Length=c.value('Length(1)','numeric(18,0)') ,
        Width=c.value('Width(1)','numeric(18,0)') ,
        Height=c.value('Height(1)','numeric(18,0)') 

    FROM @xml.nodes('/NIACList/NIAC/CommercialUnit/MobileUnit') MobileUnit(c)

The problem is, that i gain such error on executing the query:Error converting data type nvarchar to numeric.

Any ideas to solve this problem?