Get list of user roles

Hi guys,

I'm using metabox to get a list of users which is great

array(
    'id'   => $prefix . 'user',
    'type' => 'user',
    'name' => esc_html__( 'Users', 'wtw' ),
    'desc' => esc_html__( 'Select users who can view this contact information.', 'wtw' ),
    'field_type'  => 'checkbox_list',
    'placeholder' => 'Select an author',
)

But is there a way to select user roles?

Thanks in advance