example.js

// https://igorescobar.github.io/jQuery-Mask-Plugin/docs.html#translation
$('.gdefile-mask').mask('FILE-0000-00000000-MTCA-PRODUCTION-#SEMSECTOR', {
    'translation': {
        'A': { pattern: /A/, fallback: 'A', optional: false },
        '#': { pattern: /#/, fallback: '#', optional: false },
        'S': { pattern: /S/, fallback: 'S', optional: false }
    },
    placeholder: "FILE-____-________-MTCA-PRODUCTION-#SEMSECTOR"
});