This durable cloth adapter with two D-rings is designed for supporting your two piece Lumedyne Cyclers and their attached Battery by a shoulder strap since those Cyclers did not include any shoulder strap D-rings.
This high voltage Cycler attaches onto any of the Lumedyne Batteries which are sold separately. Photographers who need a lot of flashes per charge and want bigger batteries than what are built inside the single piece Cyclers will prefer these even though they are slightly larger, they do offer two HV output jacks so they can run two flashes even without needing a Y cable. These have a Low Battery Warning but no battery gauge. They indicate when they are recycling.