This is exactly what you say! If you specify this: `'number:0:4'`, it will generate `input type=number min=0 max=9999 maxlength=4`. If you specify this: `'number:0:4:2'`, it will generate `input type=number min=0 max=99 maxlength=4`. Understand? Max is optional. But it can be replaced, so that you specify it directly (which gives us more freedom): 'number:0:4:99'. This would mean, you can specify: 'number:0:4:128' and it would generate `input type=number min=0 max=128 maxlength=4`