mask.js

// capKey vem de uma iteração em um objeto
$('#div' + capKey).find('input')
  .keydown(e => {
    const key = e.key
        , arrKeys = [
            'ArrowDown', 'ArrowLeft', 'ArrowRight', 'ArrowUp','Backspace',
            'Control', 'Delete', 'End', 'Home', 'Tab'
          ]
         , input = $(e.currentTarget)

    if(key === 'Backspace'){
      delCount++
    }

    if(delCount > 4 && input.length < 5){
      intDecimal = input.val().length
      count = true
    }

    if(arrKeys.includes(key))
      return

    if(input.val() === ''){
      count = true
      intDecimal = 0
    }

    if((e.ctrlKey || e.metaKey) && ('a' || 'c' || 'v' || 'x')){
      return
    }

    if ((e.shiftKey || (e.keyCode < 48 || e.keyCode > 57)) && (e.keyCode < 96 || e.keyCode > 105))
      e.preventDefault()

    if(intDecimal === 5){
      input.val(input.val() + '.')
      count = false
      intDecimal = 0
    }

    if(input.val().length > 11)
      e.preventDefault()

    if(key.match(/[a-zA-Z]/))
      e.preventDefault()

    if(count)
      intDecimal++
  })