In the main they seem to get it wrong the other way around, with 110 volt we don't have a neutral so all 110 volt stuff for UK site use should have L1 and L2 not L and N, yet most yellow plugs still have L and N. Even yellow cable has brown and blue instead of brown and black which would be right colours for British 110 volt site equipment.
As said likely the moulded part is used for more that just that switch so the numbers L1 and L2 are used. OK since a 230 volt neon it will not be used with L1 and L2 with that neon but it could be with other uses.
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