packages/usa-file-input/src/test/template.html
<div class="usa-form-group">
<label class="usa-label" for="file-input-specific">Input accepts only specific file types</label>
<span class="usa-hint" id="file-input-specific-hint">Select PDF or TXT files</span>
<input id="file-input-specific"
class="usa-file-input"
type="file"
name="file-input-specific"
aria-describedby="file-input-specific-hint" accept=".pdf,.txt"
multiple
/>
</div>