This stainless steel casing prevents leaking through the center of rivet. It is also used to replace rivets in worn, oversized holes, as in Hobie® castings and sidebars. For 3/16" diameter rivets up to 5/8" penetration. Requires 13/64" hole. This casing is suggested for use with #19-5022 (MCP 6-6) rivets with steel mandrels because they pull tighter than rivets with stainless mandrels. Compare to Hobie Cat® #8011291.