The Sea to Summit Spark -1C/30F Down Sleeping Bag - Regular invites adventurers to experience unparalleled comfort and warmth on their journeys. This meticulously crafted sleeping bag features RDS-certified, 850+ fillpower goose down, treated with a non-PFC Ultra-Dry Down to ensure optimal insulation even in damp conditions. Its ultralight design makes it a breeze to carry, while the breathable 10D nylon liner and shell, both treated with PFC-free DWR, guarantee a cosy and dry night's sleep. The technical hood, anatomical footbox, and ergonomic mummy shape provide tailored comfort, ensuring a restful sleep, while the reliable YKK #5 zippers offer durability and ease of use, making it a perfect companion for any adventure.

Sea to Summit Spark -1C/30F Down Sleeping Bag - Regular Features:

• RDS-certified, 850+ fillpower goose down with a non-PFC Ultra-Dry Down treatment: Delivers superior warmth-to-weight ratio and maintains insulation in damp conditions.
• Ultralight: Ideal for backpacking and minimalist adventures, ensuring minimal weight without compromising on comfort.
• Breathable 10D nylon liner and a 10D shell with PFC-free DWR: Provides excellent ventilation and water resistance, keeping you dry and comfortable.
• Technical hood, anatomical footbox and an ergonomic mummy shape: Designed to enhance fit and comfort, offering a snug and natural sleeping position.
• YKK #5 zippers: Robust and smooth-operating zippers ensure easy access and long-lasting performance.

Optimised for minimal weight and maximum warmth, the Sea to Summit Reactor Lightweight Sleeping Bag Liner boosts your sleep system performance without adding unnecessary bulk. Built with advanced Thermolite® Pro fabric, it uses infrared-absorbing ceramic pigments and hollow-core fibres to trap body heat and add up to 4°C of extra warmth. The stretch-knit construction and shaped arm openings allow natural movement through the night, while the ergonomic hood enhances thermal efficiency without feeling restrictive. Treated with HeiQ Fresh odour control, the Reactor Lightweight stays fresher for longer, dries quickly, and helps extend the life of your sleeping bag by reducing wash frequency. Designed for backpacking, cycle touring, and paddle touring, it’s a compact, technical liner for ultralight adventures.

Sea to Summit Reactor Lightweight Sleeping Bag Liner – Key Features

• Thermolite® Pro insulation: Hollow-core fibres and infrared-absorbing pigments enhance warmth with minimal pack size.
• Adds warmth: Increases sleeping bag performance by up to 4°C.
• Stretch comfort: Stretch-knit fabric fits any sleeping bag shape and allows unrestricted movement.
• Technical hood design: Ergonomic hood improves warmth without adding bulk.
• HeiQ Fresh odour control: Helps keep the liner fresh after extended use.
• Sleep system integration: Shoulder snap connectors pair with compatible Sea to Summit sleeping bags.
• Machine washable: Easy care construction reduces wear on your sleeping bag.
• Lower impact materials: Made with certified recycled fibres and bluesign APPROVED materials.

Specifications – Reactor Lightweight Sleeping Bag Liner

• Best Use: Backpacking, Cycle Touring, Paddle Touring
• Type: Thermal Liner
• Material(s): 100% Post-Consumer Recycled Polyester
• Stuff Sack Material: 100% Polyester
• Temperature Boost: Up to +4°C

Available Sizes

• Short
  Weight: 235 g
  Dimensions: 178 x 80 cm
  Packed Size: 10 x 18 x 10 cm
  Fits Up To Height: 170 cm
• Regular
  Weight: 255 g
  Dimensions: 193 x 80 cm
  Packed Size: 10 x 18 x 10 cm
  Fits Up To Height: 185 cm
• Long
  Weight: 270 g
  Dimensions: 206 x 80 cm
  Packed Size: 10 x 18 x 10 cm
  Fits Up To Height: 198 cm

The Sea to Summit Evac Compression Dry Bag UL – 20L provides high-capacity waterproof compression storage for extended backpacking and paddle sports adventures. Built from bluesign APPROVED Ultra-Sil 30D Cordura® nylon with a non-PFAS DWR finish, it protects gear from rain and spray while allowing trapped air to escape through the EVAC fabric base. The reinforced roll-top closure and four-strap compression system enable even, secure packing of larger soft items.

Sea to Summit Evac Compression Dry Bag UL – 20L Key Features:

• Large capacity storage: 20 litres for sleeping bags, insulated jackets or bulkier gear.
• EVAC air-permeable base: Allows compression without purge valves.
• Reliable waterproofing: Roll-top closure with patented Field Repair Buckle.
• Even four-strap compression: Prevents bulging and maximises space efficiency.
• Ultralight yet durable: Ultra-Sil 30D Cordura® nylon construction.
• Sealed seams: Double-stitched and tape-sealed for dependable protection.

Specifications – 20L

• Best Use: Backpacking & Paddle Sports
• Capacity: 20 Litres
• Weight: 110g
• Dimensions: 24.2 x 24.2 x 47.6 cm
• Closure: Hypalon roll-top with compression straps

Offering maximum compression and generous capacity, the 20L Evac Dry Bag is ideal for protecting and compacting larger gear inside your pack.

The Sea to Summit Circuit Down Sleeping Bag -1°C | 30°F – Long is designed for taller adventurers who want space, warmth and versatility in a lightweight 2-season package. Its semi-tapered rectangular profile provides additional width for side sleepers while maintaining efficient thermal performance. Filled with 650+ fillpower Ultra-Dry Duck Down and built with hybrid box-baffle construction, it delivers consistent warmth with minimal weight. The wraparound zip allows complete ventilation control and can open fully to create a flat quilt for warmer conditions.

Sea to Summit Circuit Down Sleeping Bag -1°C | 30°F – Long Key Features:

• Extended fit: Designed to suit users up to 198 cm tall.
• 2-season performance: ISO lower limit rated to -1°C.
• Premium 650+ fillpower down: RDS-certified Ultra-Dry Down ensures warmth and packability.
• Hybrid baffle construction: Prevents down shifting and cold spots.
• Full wraparound zip: Enables maximum airflow and full quilt conversion.
• Thermal draft collar: Reduces heat escape for improved warmth retention.
• Soft 20D fabric: Lightweight and comfortable against the skin.
• Durable YKK zipper: Anti-snag design for smooth operation.
• Responsible materials: Bluesign APPROVED recycled fabrics and non-PFAS treatments.

Specifications – Long

• Best Use: Backpacking, Camping, Travel
• Performance: 2 Season
• ISO Lower Limit: -1°C
• Weight: 910g
• Compression Sack: 13L
• Fits Up To Height: 198 cm

Offering extra length without excessive bulk, the Long Circuit is a dependable and adaptable option for taller campers and backpackers.

The Sea to Summit Hamelin Synthetic Sleeping Bag -1°C | 30°F – RCS – Regular is a performance-oriented synthetic sleeping bag built for trekking, backpacking and damp-weather adventures. Designed with a relaxed Contour shape, it provides room to move comfortably, making it ideal for side sleepers without creating cold spots. Layers of Revive Loft synthetic insulation are strategically placed to maximise warmth retention, while recycled bluesign APPROVED fabrics ensure durability with reduced environmental impact. Featuring the versatile Free-Flow zip system, the Hamelin adapts easily to changing conditions by allowing full ventilation or opening flat as a quilt.

Sea to Summit Hamelin Synthetic Sleeping Bag -1°C | 30°F – Regular Key Features:

• Reliable 2-season warmth: ISO tested lower limit rating of -1°C for dependable cool-weather performance.
• Damp-condition ready: Synthetic Revive Loft insulation maintains warmth even in wet environments.
• Contour shape: Relaxed mummy design offers space for side sleeping while retaining thermal efficiency.
• Free-Flow zip system: Full-length side zip with double sliders extends through the footbox, plus secondary side zip for ventilation and arms-free functionality.
• Draft protection: Technical hood, draught collar and draught tubes reduce heat loss on cooler nights.
• Snag-free operation: YKK #5 zipper with zip plough ensures smooth and reliable use.
• Packable synthetic build: Compresses to 8.4L packed volume for manageable storage.
• Responsible materials: 100% RCS-certified recycled insulation and bluesign APPROVED fabrics with non-PFAS DWR.
• 1% for the Planet product: Supports biodiversity conservation initiatives.

Specifications – -1°C Regular

• Best Use: Light Trekking, Backpacking (especially wet conditions), Paddle Touring, Car Camping
• Performance: 2 Season
• ISO Lower Limit: -1°C (30°F)
• Women's ISO Comfort: 3°C
• Weight: 1124g
• Compressed Volume: 8.4L
• Compression Sack: 20L included
• Fits Up To Height: 185 cm
• Insulation: RCS-certified recycled multi-denier synthetic (Revive Loft)
• Shell: 20D recycled polyester with non-PFAS DWR
• Liner: 20D recycled polyester

Built for reliability when conditions turn damp, the Hamelin -1°C Regular offers adaptable ventilation, recycled construction and dependable synthetic warmth for a wide range of backcountry adventures.