First, let me say that the concept of this kit is really great. The amount of materials included is adequate for its purpose. The timer, while difficult to understand and lacking greatly in programming flexibility, does an adequate job of controlling the water. But.... The drippers are J, U, N, K. JUNK!!! I set this system up to water a total of six containers, using 2 drippers in each of the 4 larger containers, and 1 each in the smaller containers. The test run with the timer on manual performed as expected, except 1 of the 2 drippers in 2 of the large container didn't operate properly. After 30 minutes of operation, 1 dripper hadn't emitted any water, and the other failed dripper had allowed less than (guessing here) about a CUP of water. The other dripper in each of the 2 failed pairs had emitted a decent amount of water. I am not sure is was the amount promised (should have been around a quart) but it seemed to be working OK. One of the single drippers was OK, (container 6). But the other single one was allowing very little water to pass, (Container 5). Specifications of the installation are: Water pressure at faucet was between 45-50 pounds PSI. Total run of the tubing was about 30-feet. Total number of installed drippers was 10, in groups of 2,2,2,2,1,1. The containers with the double drippers were closest to the timer, and the single drippers at the end of the run. The Initial failed drippers in the twin groups were in containers 2 and 3. and the single container failure was in container 5. Container 6, the farthest from the timer actually was outputting the greatest amount of water. I double checked the 1/4-inch water line to verify there were no kinks, and only 1 very slight leak at dripper #10. (This was the dripper in container 6 that WAS emitting water. ) Becoming frustrated with the significant inconsistencies of the system, I decided to swap out the inoperative drippers with some of the unused ones. After removing each inoperative dripper., (I cut the 1/4-inch tubing very close to each of the drippers, and water flowed from the tube with significant force.) I installed a new dripper in each failed location. (One at a time to test water pressure and dripper flow after each change, and learned that one of the replacement drippers also did not function. ) Fortunately, I was able to find 10 good ones out of the batch of 20 included in the kit, and retested the system. Finally, the system seemed to be operating properly. I set the timer to turn on every 6 hours, and run for 20 minutes. This gave 4 watering cycles a day for a total operating time of 80 minutes. At dripper rating of 1/2 gallon per hour, this should have output a bit more than a gallon a day, per dripper. This would put 2 gallons/day in the large containers and about a gallon/day in the small containers. I was concerned that this may have been over-watering the containers. But each was filled with a mixture of potting soil, compost, and about 25-30% of real garden dirt; and each container had drain holes to prevent flooding. I also felt that knowing the drainage abilities of the soil and the containers, and that July was generally a hot month in Missouri, over-watering was much less of a threat to the plants than under-watering After a 2nd successful test run, and another 24 hours on automatic, I felt confident that it would keep my veggies and flowers in good shape while I was away from home for 8 days. On departure day, I double checked all the drippers with a quick 10-minute manual cycle. All seemed normal. When I returned, the plants in container 1 and 2 (2 drippers each) were dry, and the plants looked a bit dry, too. The plants in container 3 were VERY dry and wilted. I lost 3 of the 4 plants in that container. Container 4 was fine. Plants looked healthy, and the soil was damp. Container 5 was flowers, and they were dry and wilted; but not yet dead. (Heavy watering for a couple days brought most back.) Container 6 was flowers, and they were doing fine. I immediately turned the timer to manual to see what the trouble was, and water flowed all the way through to container 6. But predictably, the plants with poor appearance were getting little or NO water. I hand watered everything that was dry with the garden hose and when the timer was checked the next day, it was operating on the anticipated schedule. The moral of the story is that the quality of the REALLY IMPORTANT part of the kit is unreliable, and not to be trusted. (Hence, the 1-star rating.) If I could return the kit, I'd do so. But the return window had passed. As I am stuck with this system, I will attempt to locate some drippers locally that are made by a different manufacturer and see of I can save the system. I've invested a lot of time and energy to just tear it all out and throw it in the trash.