Sea to Summit Spark

Yes, the 30°F rating is accurate for most sleepers, provided you are using an insulated sleeping pad with an appropriate R-value. Because this is an ultralight bag, it relies on your pad to insulate you from the cold ground.

The Spark features a slightly more generous cut than traditional, restrictive mummy bags. While it remains efficient for heat retention, it offers enough room to shift positions without feeling overly confined.

The 10D nylon shell features a PFC-free DWR coating that effectively sheds light condensation and moisture. However, it is not waterproof, so it is best used inside a tent or bivy rather than exposed to direct rain.

Yes, Sea to Summit uses Responsible Down Standard (RDS) certified down. This ensures the insulation is ethically sourced and traceable throughout the supply chain.

To preserve the longevity of the 850+ fill-power down, avoid keeping the bag compressed in its stuff sack for long periods. Store it loosely in a large cotton or mesh storage bag when you are not on the trail.

Yes, the updated design includes reinforced protection at the hood and foot box. These areas are most prone to condensation buildup in lightweight shelters, so the added durability helps keep the down dry where it matters most.