The Thermarest Vesper 45 UL is an ultralight backpacking quilt for summer thru hiking. It's the lightest option in the top-rated Vesper quilt line.
Thermarest says:
For the lightest possible pack, we crafted the Vesper 45F/7C to deliver the essential warmth needed for mild-weathered pursuits. To keep it light, we used powerful 900 fill Nikwax Hydrophobic Down certified by the Responsible Down Standard. Designed with high-quality materials and Therm-a-Rest performance features like SynergyLink™ connectors, a snap neck closure, perimeter side baffles and an insulated footbox provide warmth and comfort in the backcountry. When compared to sleeping bags, the Vesper quilts save weight and pack smaller by utilizing the warmth of your insulated pad. Storage sack and compression stuff sack included.
Therm-a-Rest's Vesper 45 UL Down Quilt is one of our lightest quilts, with a comfort limit of 7°C. This outstanding warmth to weight ratio is achieved by using the highest quality responsibly sourced down expertly zoned in a box wall construction. The quilt is lined with ThermaCapture to trap body heat keeping you warm. This is a lightweight option for boosting the warmth of your current sleep system by simply adding the Vesper as a throw over blanket, for example.
The foot box to is quite narrow but this helps with a close fit around the end of your mat. There is a single (potentially flimsy) strap to keep the quilt attached to a sleeping mat to help hold in your body warmth. The strap can be removed if you want to save a few grams. As you would expect with such a lightweight quilt the pack size is very small.