Paddy and Mick were both laid off, so they went to the unemployment office. When asked his occupation Paddy answered, "Knicker Stitcher. I sew da elastic onto ladies knickers and thongs."
The clerk looked up "Knicker Stitcher" on his computer and, finding it classified as unskilled labor, he gave him $80 a week unemployment pay. 

Mick was next in line and when asked his occupation, he replied, "Diesel Fitter." Since a diesel fitter was a skilled job, the clerk gave Mick $160 a week.

When Paddy found out he was furious. He stormed back into the office to find out why his friend and co-worker was collecting double his pay. The clerk explained, "Knicker Stitchers are unskilled labor and Diesel Fitters are skilled labor." 

"What skill?" yelled Paddy. "I sew da elastic on da knickers and thongs, then Mick puts em over his head and says: Yep, dees'll fit 'er.