Used Redrock Micro Riser V2, 15mm Rod Support, Quick Release version

The microRiser - Quick Release version is a multi-purpose clamp that allows you to attach a second set of rods at a fixed height above or below your current rods, and quickly attach/remove them with the quick release clamp.

This clamp is most often used for raised front rails on taller HDSLR cameras to adapt accessories such as the microFollowFocus and microMatteBox at the correct height. Use shorter 15mm rails such as 4" or 6" carbon fiber rails. It can also be used to quick release components such as low-slung handlebars.