Big Horn 19835 ProGrip Side by Side Adapter - Set of 6. By using the Z brackets in this ingenious Big Horn ProGrip Connector Kit, two ProGrip clamps can be attached to each other side by side (one inverted and one right side up), thus creating an unchanged height profile while keeping both handles at the same end. Various length clamps can even work together to allow you to effectively create a strong, extra wide work surface if needed. For use with our Big Horn ProGrip Straight Edge Clamps. Each kit includes six Z brackets.