Safety is paramount when Consumer Reports tests strollers because, of course, they carry precious cargo. So when we discovered a problem in our routine stroller tests with the Combi Shuttle 6100 Travel System, we immediately contacted the manufacturer and the Consumer Product Safety Commission to make them aware of the concern. After we told Combi that the infant car seat was detaching from the stroller under certain circumstances, the company stopped selling the stroller (Combi told us this model was sold only online) and began its own analysis. Though we commend Combi for its fast action, we worry that families who already own this Combi travel system may still face a safety risk, and because strollers often end up on the secondary market for used baby gear, we have designated the Combi Shuttle 6100 Travel System a Don’t Buy: Safety Risk.

Combi assures us that it’s working with the CPSC in addition to doing its own testing. Here’s how we reached our decision.

How We Tested

Consumer Reports bought three Combi Shuttle 6100 Travel Systems, which combine an infant car seat and a stroller (two systems for $306 each and one system for $380), and put them through a battery of tests patterned after the standard industry test for strollers. One of the tests involves slowly tipping the travel system over three different ways: to the front, to the back, and to one side. The test is used to verify whether the car seat stays securely attached to the stroller when it’s tipped past its center of balance.

With each of the three strollers, the car seat stayed in place when the stroller was tipped forward or backward. But on every sample, when the unit was tipped to the side, the car seat frequently detached completely when hitting the ground. That happened multiple times when the stroller was tipped to the right or the left. Though we know of no injuries associated with this Combi travel system, we believe the problem poses a potential safety risk.

Until recently, there were no federal safety standards for strollers. That changed when mandatory safety standards took effect for strollers manufactured after Sept. 10, 2015. Of the three Combi Shuttle 6100 Travel System strollers we purchased for our tests, two were made in July 2015 before the standard became mandatory and the third was made in May 2016 after the new standard took effect. All three performed similarly in our tests. Out of the 15 travel systems in our stroller ratings, the Combi Shuttle 6100 Travel System is the only one that exhibited this type of problem.

What You Can Do

If you already own the Combi Shuttle 6100 Travel System, we recommend that you stop using the stroller with the car seat attached. You can safely use the car seat in a vehicle. In fact, the Combi Shuttle infant car seat is one of 10 recommended models in our car seat tests. It was one of the better infant car seats overall for balancing crash protection, ease-of-use, and vehicle fit, and scored 77, ranking it fourth overall among infant car seats.

If your baby is 6 months or younger, you shouldn’t place him or her in the Combi Shuttle 6100 stroller itself; the stroller is not designed for babies that young. If your baby is 6 months or older and can sit up, the stroller on its own passed all of our tests and can be used without the car seat.

Parents of young infants who already own the Combi travel system may wonder what to do. As a possible economical solution, we tested the Combi Shuttle car seat in the Baby Trend Snap N Go GX Universal Infant Car Seat Carrier, $90, and found that it is a viable alternative. It is a recommended model, and in our tip-over tests, the car seat stayed securely in place.

However, parents should be aware of a few drawbacks with this stroller. Without using the included “universal” car seat adapter frame, only Baby Trend SnapFit-equipped car seats can click into the Snap N Go GX directly. Other compatible infant car seats, including Combi’s, require use of the adapter frame. The infant car seat is placed on top of this frame and secured using a strap through the car seat’s belt path; this isn’t as convenient as simply snapping in a seat. And on each of two tested samples of the Snap N Go GX, we noted that the front wheels tend to hesitate, especially when you change direction.

If you like the convenience of a travel system, there are recommended options from our tests. Our top-rated model is the Graco Stylus, $280. The Chicco Cortina KeyFit 30 travel system, $300, also earned an excellent score. We will continue to communicate with Combi and the CPSC about this travel system and report on any developments.