Review on Seesii Gym Timer: LED Interval Clock For Crossfit, Countdown/Up Stopwatch With Remote & Power Bank Support - Perfect For Home Gyms! by Derek Evans

The unit requires the remote to set clock time, intervals etc. The remote takes 2 AAA batteries. One battery fit into the remote just fine. The 2nd battery wouldn't fit and I didn't want to break the spring or the remote cover forcing it in. I emailed SeeSiiUS customer service and haven't heard back from them to acknowledge my email even after a day. The phone number on their website (SeeSiiUs.com, 18926074757) is not a valid US number. I will be returning this item because of poor quality and non-existent customer service.