This is a replacement Synergy Battery Strap Set, and is intended for use with the Synergy E6 and E7 helicopters.
Tuesday, Sep 24 2019 (about a year ago)
Synergy Battery Strap Set (3)
At the time I purchased these, they are Blue - Not Black as pictured. My helicopter kit came with blue straps and I was hoping to use the color difference to identify Battery #2 but had to mark the battery instead. No biggie. Definitely a strong hook and loop design. I won't hesitate to purchase again for battery #3.