a blow molded , thin walled plastic container for filling with a liquid whose temperature is elevated above ambient . the container includes a first portion of a first diameter , a second portion of a second diameter , and reduced diameter region between the first and second portions . the reduced diameter portion extends circumferentially around the container and a plurality of ribs which are located to extend between the first and second portions . the ribs form reinforcing members in the reduced diameter portion and increase the top load capabilities of the container . the first and second portions can both be formed in the shoulder portion of the container or one in the shoulder portion and one in the sidewall of the container .