Those pull tabs/ring pulls are the early style (1960s - 1970s), so you are likely to find some coins that age or earlier. They typically show up in the high 20s to low 30s on the Nokta Legend. Sometimes found detached, causing a separate signal for the tab and ring. I learned from the smart guys here they are called "beaver tails".
If you're hunting for gold, you’ll have to dig some tabs - there’s no perfect way to filter them out. They have similar conductivity. I have a few strategies that I use depending on the location. One strategy is to notch out 20 to 30 on the Legend, but you'll miss some smaller jewelry due to over lapping VDI.
Increase iron bias - It helps distinguish aluminum from potential gold. Use 60 tone mode - Gold tends to have a smoother, more rounded tone than pull tabs, which sound choppier (SP?). Check depth readout -Many tabs sit shallow (1-3 inches), while gold items are often deeper.
As a relative newbe, the biggest and best piece of advice I can give you is to swing slow, that a bouncing VDI is likely trash, and dig it all until you understand your detector. Good luck and HH.
Mark in Michigan