public function checkbox_bool() {
			$field = $this->do_field_start();
			$field .= $this->do_field_label();
			$field .= $this->do_field_div_start();
			$field .= '<input type="checkbox"';
			$field .= $this->do_field_name();
			$field .= ' value="1" ' . checked( $this->value, true, false );
			$field .= $this->do_field_attributes();
			$field .= '/>';
			$field .= $this->do_screen_reader_label();
			$field .= $this->do_field_div_end();
			$field .= $this->do_field_end();

			return $field;
		}