It's a 12hr continental shift, meaning....: In a pay cycle (2 weeks), I work a total of 7 days. So if you can follow this (most have problems...lol):

The cycle starts with: Mon/Tues "on" or "working", Wed/Thurs "off", Fri/Sat/Sun "on", It then flips for the following week. Mon/Tues "off", Wed/Thurs "on", Fri/Sat/Sun "off".

Over the long weekend off it flips to nights and then repeats the cycle. So on and so forth. It's not the best schedule, but if you do the math I only work half the year, and taking vacation days in the right spots gives you excessive amounts of time away from the daily grind. The trick is to get nap time in during the midnights so your not completely changing your sleep cycle all the time. I don't know how the production people do it.