protected static function get_sanitize_callback( $sanitize_cb ) {
		/**
		 * Filter the value before it is saved.a
		 *
		 * @param bool|mixed     $check      The check variable.
		 * @param mixed          $value      The value to be saved to this field.
		 * @param int            $object_id  The ID of the object where the value will be saved.
		 * @param array          $field_args The current field's arguments.
		 * @param \CMB2_Sanitize $sanitizer  The `CMB2_Sanitize` object.
		 *
		 * @return mixed
		 */
		return function( $check, $value, $object_id, $field_args, $sanitizer ) use ( $sanitize_cb ) {
			if ( $field_args['repeatable'] ) {
				return Utils::filter_blank(
					is_array( $value ) ? array_map( $sanitize_cb, $value ) : []
				);
			}

			return $sanitize_cb( $value );
		};
	}