MetalTech 21.75 in. x 10 in. x 16.75 in. Aluminum Adjustable 2-Rung Ladder Jacks for Scaffold Extension Boards or Ladder, (2-Pack) E-LJ20P - The Home Depot
Ladder Jack Scaffolding - Long Body - Southwest Scaffolding & Supply, LLC
Guardian Fall Protection 2420 Two-Rung Short Body Ladder Jack, Silver - Ladder Accessories - Amazon.com
Guardian 2430 3 Rung Long Body Aluminum Ladder Jack