This front sight base is made to fit the 14mm barrel wich is the most common size among the G43 and K43 rifles.

14mm ≈ 0.55 inch

There are a few G43 and K43's fitted with a 15,5mm front sight base, unfortunately we do not produce these at the moment, however if you really need one and we can put you on a list and if we have enough costumers we van start producing these. 

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