# File lib/ec2/right_ec2_reserved_instances.rb, line 80
    def describe_reserved_instances_offerings(*list_and_params)
      list, params = AwsUtils::split_items_and_params(list_and_params)
      # backward compartibility with the old way
      list ||= Array(params[:aws_ids])
      rparams = {}
      rparams.update(amazonize_list('ReservedInstancesOfferingId', list)) unless list.blank?
      rparams['InstanceType']       = params[:aws_instance_type]       if params[:aws_instance_type]
      rparams['AvailabilityZone']   = params[:aws_availability_zone]   if params[:aws_availability_zone]
      rparams['ProductDescription'] = params[:aws_product_description] if params[:aws_product_description]
      link = generate_request("DescribeReservedInstancesOfferings", rparams)
      request_cache_or_info(:describe_reserved_instances_offerings, link,  QEc2DescribeReservedInstancesOfferingsParser, @@bench, list.blank?)
    rescue Exception
      on_exception
    end