Jumper Box Tubing

A Jumper BoxTM is a jockey box without its faucets. This difference allows you to customize the setup of your draft beer system by having the location of your beer taps separate and away from the brains of the operation—your Jumper BoxTM

Whether you decide to install a draft tower as a countertop feature inside your mobile bar or as taps on the exterior of your beer trailer, you have to account for beverage tubing and gas lines. 


Just like at your favorite brewery or restaurant, beer doesn’t magically transport itself from its keg to your glass. We’re working on that tech right now with Elon, however. Anyway, your beer must travel through beverage lines (i.e.,vinyl tubing)—known as “jumpers.”

For Jumper BoxesTM, you need two sets of beverage lines:
  1. Keg Jumper: Tubing (generally longer) that carries beer from its keg to your Jumper BoxTM
  2. Shank Jumper: Tubing (generally shorter) that carries beer from your Jumper BoxTM to your faucets (taps) via a connecting *faucet shank  

*A faucet shank is a stable unit that either gets housed inside a countertop draft tower or is the tunnel from the inside of your beer trailer to its exterior wall that allows for you to install taps to the outside of your trailer. Faucet shanks support the connection between Shank Jumper and beer faucet.

Note: Both the Keg Jumper and Shank Jumper are vinyl beverage tubing, constructed identically. Their only difference should be their diameter (explained below). We (COLDBREAK®) have taken the liberty to assign them names to distinguish their location and purpose in the setup.

shank jumpers hooked up to jumper box


Your beer trailer is going to be designed and set up differently than her mobile bar. And while we can’t predict or account for every possible scenario, there are a few things to consider when you’re building yours.

Tubing Diameter

Without getting too scientific, we have to control the flow of beer via the CO2 pressure that forces it up and out of its keg with an appropriate diameter of our beverage lines. Otherwise, your beer will either dribble or blast out of your faucet. Like Goldilocks, we want to avoid both extremes, and instead need something in between and just right.

Our recommened Keg Jumpers are 5/16” ID (i.e., its internal diameter). 

FYI, your beer then travels through stainless steel coils that are 5/16” OD (i.e., its external diameter). Their ID is 1/4".

When beer exits a Jumper BoxTM, it needs to transfer into a Shank Jumper that is equal to or smaller (never larger) than the coils’ internal diameter.

The Shank Jumper should be 1/4" ID (matching the coils), or 3/16” ID (one measurement smaller). 

Pro tip: To help maintain the liquid’s proper serving temperature as it leaves the chilled coils and combats ambient temperature, we recommend insulating your Shank Jumper with a piece of basic pipe foam (see photo).

keg jumpers attached to kegs

Tubing Length

By default, most beverage lines come in 4’ or 6’ lengths. This gives more than enough leeway for the vast majority of mobile bar trailers to be flexible in their setup. For those who want to tidy up their tube spaghetti aesthetics, you can easily trim their length on your own at home. Reattaching the tailpieces and end clamps is self-explanatory and easy.



Regular cleaning is essential to ensure that the product being served to your guests maintains its integrity in quality, flavor, and presentation. In addition, the importance of adhering to proper sanitation standards is critical. Guests expect (and deserve!) that what they’re drinking out of your mobile bar tastes exactly the same as it should coming straight from their favorite taproom. 

In all seriousness, if this is something you’re not willing to maintain, stop now—pack up shop, and go home. Yes, it’s that big of a deal. 

Every Two Weeks (14 days):

  • Clean Keg Jumpers and Shank Jumpers
  • Disassemble and clean faucets
  • Clean keg couplers 

For a practical tutorial, watch our how-to video, How to Clean a Jockey Box.


Both your Keg Jumpers and Shank Jumpers should be replaced every one to two years, or sooner if you experience any bacterial contamination (from not cleaning regularly) or off-flavors.  

To that point, if you’re dispensing root beer, intensely-flavored beers, margaritas, wines, or cider—generally anything with aggressive sugar content, flavor, or color—you should be replacing your beverage lines after each use. So, let’s say you regularly cater weddings and you have a 4-tap Jumper BoxTM. It’s a smart play to designate each line for distinctly different beverages. For example, two lines could be beer, one for white wine or a mixed cocktail, and the last one for alcohol-free soda.  


For draft beverage novices, don’t fret—after your system is properly installed and set up, and once you’ve done one cleaning cycle, proper care and maintenance will feel like second nature.

While there will probably be waaay more information than you’ll ever need, if you’d like an in-depth dissection of all things draft beer systems, reference these two trusted, downloadable publications from the Brewers Association: Draught Beer Quality for Retailers, and the technical and scientific-heavy rabbit hole, Draft Beer Quality Manual.