I work 6 days on and 4 days off.
My 6 days consist of:
2 x early shifts (7.30am - 4.30pm)
2 x late shifts (3pm to midnight midweek or 4pm to 2am Fri and Sat)
2 x night shifts (11pm to 8am midweek or 8pm to 8am Fri and Sat)
My first day off is always straight off a night shift, so I suppose its more like 3 and a bit days off.
The nature of my work however means that I can often get kept on and / or have a quick turnaround.
Last week for example I started work at 7.30am on Wednesday and then finally finished at 1am the following day on Thursday. I was then back in at 7.30am on that same day.
It's also common to have your shifts changed or hours increased due to 'operational demands.'
Not complaining though as I enjoy my job