The 4013 single stack is on the large frame.
The 4013TSW double stack is on the medium frame. They made them without a rail (pre-rail) & later with a rail.
Without a doubt the 4013 is the stronger.
The 4013 weighs 29.5 oz & the 4013TSW pre-rail weighs 27.5 oz, both wearing Hogues.
I have, & like, both but the 4013 is my favorite.
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4013TSW & 4056TSW (pre-rail)
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4013 vs 4013TSW barrel -01
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4013 vs 4013TSW barrel -02
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4013 vs 4013TSW barrel -03
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