The PEXRITE® #708 POP-UP™ supports up to three 3/8" O.D. or two 1-1/8" O.D. flexible tubing lines (PEX or softer copper). Ideal for positioning tubing prior to concrete slab pouring. For elevated slabs, nail bracket to form decking or edge form. For slab-on-grade (ground work), secure bracket with #4 rebar driven into the ground.