Ceramic honeycomb structural body

A monolithic catalyic converter, comprising:

• a housing;
• a ceramic, honeycomb structural body disposed within said housing, said body having two end surfaces and a plurality of channels extending through the body between the end surfaces, each of said end surfaces having an inner circumferential portion and an outer circumferential portion contiguous with and extending radially outwardly from the inner circumferential portion;
• a plurality of annular supports within said housing for contacting each of the end surfaces of said structural body;
• substantially perpendicular to the axis of said parallel channels:
• clamping means for applying pressure to said annular supports to clamp said end surfaces, each of said outer circumferential portions having a first portion contiguous with said inner circumferential portion and having a surface parallel to and abutting one of said annular supports, and a second portion radially outward of said first portion having a surface which is not parallel to said support and which is spaced from said supports, the pressure applied to said first portion being greater than the pressure applied to said second portion.