Kowalewski has appeared in 13 NFL games with two starts, all with the New York Jets. He has five career catches for 18 yards and one touchdown.
Kowalewski, who waived by the Jets in April of 2008, is more of an H-back than a pure fullback as he stands 6-4, 250.
The other newcomer is kicker Connor Barth, who made 10 of 12 field goals last year but was released this July when the Chiefs decided to go with seventh-round pick Ryan Succop, who made headlines in April when he became Mr. Irrelevant as the last pick in the 2009 draft.