The First Endurance EFS Liquid Shot was developed after years of research and considerable feedback from athletes. The issues raised revolved around several areas: digestion, absorption, practical use, ability to control amount used at one time, and reduction of waste. The EFS Liquid Shot provides the ingredients you need to maximize endurance and performance with exceptional uptake and absorption. Unlike a gel packet you can easily swallow a partial serving or servings at any time and the flask is reusable. Each 5oz Liquid Shot flask has a re-sealable pop-top that screws off for easy refilling and if you decide to move on from a flask, it is 100% recyclable. And First Endurance offers a 32oz refill option. The refill allows you to wash and re-use the handy and convenient flasks from this box of 6.

Each 5 ounces of EFS Liquid Shot delivers 400 high-quality calories, 1000mg of amino acids, and more than 1500mg of electrolytes so you don't need to bother taking extra electrolyte pills. It does not contain any gelling agents because First Endurance found gelling agents slowed absorption and digestion. Generally the flavors are sweet and the liquid itself thinner than gel, thicker than whole milk. The experts at First Endurance offer you the EFS line to provide energy and electrolytes in the best manner that works for you as an athlete. While it is true that runners and triathletes are more likley to use flasks, cyclists have gravitated toward the system for it's simple use, easy pocket storage, and environmental advantages over individual gel packets.