---
title: "Cumulus Junior 300"
name: "Cumulus Junior 300"
brand: "Cumulus"
description: "A thoughtfully designed children's down sleeping bag that your kids will love."
handle: "cumulus-junior-300"
sku: "CUJU300-L"
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md_url: "/p/cumulus-junior-300.md"
locale: "en"
market: "eu"
currency: "EUR"
price: 261.6
price_formatted: "€261.60"
availability: "InStock"
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category: "Sleeping bags"
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  - name: "Cumulus Junior 300"
    url: "/p/cumulus-junior-300"
last_updated: "2026-10-13"
---

# Cumulus Junior 300

Brand: Cumulus · Category: [Sleeping bags](/c/sleep/sleeping-bags.md)
Sleeping bag size: M · Zip position: Left side · Zipper position: Left

## Offer

- Price: €261.60
- Availability: In stock
- Condition: New
- Buy on the website: [HTML product page](/p/cumulus-junior-300)

## Description

A thoughtfully designed children's down sleeping bag that your kids will love. The sleeping bag is constructed from top-quality materials just like Lite Line 400. The sleeping bag is suitable for a height of 145 cm. Thanks to the drawstring, you can shorten the sleeping bag by another 30 cm, allowing the child to gradually grow into it.

Well-designed three-season children's down sleeping bag with low weight and great performance.

## Materials

The sleeping bag's construction uses **Pertex Quantum fabric 29 g/m²**, which perfectly combines low weight, durability, breathability, and packability. The outer side of the fabric is treated with a **permanent DWR (Durable Water Repellent) coating** that holds back light condensation or a few drops of water.

The excellent performance is provided by **300 grams of goose down with a fill power of 850 cuin**. The down-to-feather ratio is 95/5. The upper chambers are separated from the lower ones and are filled with slightly more down. The down distribution ratio here is 55/45. The total weight of the sleeping bag is **550 g**.

## Construction

The sleeping bag uses an **H-shaped chamber design** that prevents the formation of "cold spots" at the seams of two chambers. 

The width of the sleeping bag at the shoulders is 65 cm and 50 cm at the hips. Junior 300 is **suitable for children with a maximum height of 145 cm**. The total length of the sleeping bag is 165 cm. 

The construction of the foot box, called **Shark-fin**, prevents down compression, is comfortable, and provides better thermal performance than conventional designs.

## Features

For easy orientation, the tightening of the hood and collar is differentiated; you adjust the hood with a flat strap and the collar with an elastic band. The last chamber at the neck is filled with a larger amount of down, creating a **comfortable collar** that prevents heat loss. Inside the sleeping bag, there is a **mesh pocket** for small items.

The sleeping bag has a 130 cm long YKK zipper with 2 self-locking sliders to prevent it from getting caught in the fabric while zipping. At the feet, you will find a second slider, which is ideal for ventilation. Behind the zipper on the inside, there is a **down-filled insulating tube** that minimizes heat loss through the zipper itself. Two Cumulus sleeping bags with **opposite zippers (left + right) can be connected together**.

If the sleeping bag for a child is unnecessarily long, **you can shorten it by about 30 cm thanks to the drawstring**, so your child doesn’t have to heat extra space.

## Sleeping bag accessories

**A simple travel storage sack is included with the sleeping bag.** The sleeping bag has the shape of a cylinder with a volume of 2,8 liters and dimensions of 18/14 cm (height/diameter).

The original sack cannot be further compressed and is not waterproof, so we recommend getting a sack that solves both problems. An ideal choice is a compression sack [STS eVac Compression Dry Bag UL](/p/sea-to-summit-evac-compression-dry-bag-ul) of size 8 L or a classic waterproof bag [STS Ultra-Sil Dry Bag](/p/sea-to-summit-ultra-sil-dry-bag) about size 8 l.

**You also get a large storage bag for home use** with the sleeping bag, so the sleeping bag isn't unnecessarily compressed for a long time.

## Specs

- Sleeping bag size: M
- Zip position: Left side
- Zipper position: Left
- Chamber design: H-shaped chambers
- Down-to-feather ratio: 95/5 (feather/down)
- Filling chambers: 55:45
- Total number of chambers: 27
- Extreme temperature: -11 °C
- Season: 3-season
- Comfort temperature: 5 °C
- Limit temperature: 3 °C
- Down weight: 300 g
- Fill power: 850 cuin
- Down type: Goose
- Hydrophobic down: No
- Insulation type: Down
- Material: Pertex Quantum DWR (29 g/m², 15D ripstop nylon), YKK 5 mm zip
- Packed dimensions: 22 × 16 cm
- Maximum user length: 145 cm
- Stuff sack volume: 4 l
- Ankle width: 50 cm
- Shoulder width: 65 cm
- Weight: 550 g
- Woocommerce product id: 77026
- Brand: Cumulus

## Related

- [Cumulus Junior 500](/p/cumulus-junior-500.md)
- [Sea To Summit Ultra-Sil Dry Bag](/p/sea-to-summit-ultra-sil-dry-bag.md)
- [Sea To Summit Lightweight Dry Bag](/p/sea-to-summit-lightweight-dry-bag.md)
- [Cumulus the Quilt 300](/p/cumulus-the-quilt-300.md)
- [Cumulus Lite Line 400](/p/cumulus-lite-line-400.md)
- [Nikwax Down Wash Direct 300 ml](/p/nikwax-down-wash-direct-300-ml.md)
- [Patizon G 400](/p/patizon-g400.md)
- [Liteway Choonie Apex](/p/liteway-choonie-apex.md)

## Shipping and returns

- [Shipping and payment](/shipping-payment)
- [Returns](/return-order)

## Images

- ![Cumulus Junior 300](https://media.gramino.com/medusa/a174421dfc8013ee3f7e4e2726f146ea-01KWHVPM7TZS9MV28KSD47XJ8A.webp)
- ![Cumulus Junior 300](https://media.gramino.com/medusa/2189bc312b91f91f8065903b1b75f07d-01KWHVPMBWZ2V95PKVYHA3E7AZ.webp)
- ![Cumulus Junior 300](https://media.gramino.com/medusa/f7ab672b99948ff5c34c7118a8601555-01KWHVPMEAKEYV21HAZZ6YJQD3.webp)
- ![Cumulus Junior 300](https://media.gramino.com/medusa/363fcc0480f90a3881924b8f6d12d0e7-01KWHVPMD70EB9MD77H3HEE5YS.webp)
- ![Cumulus Junior 300](https://media.gramino.com/medusa/6c5947919e1e526a7ab96b4a5518af34-01KWHVPMGRMGXCSMBNHJ3D6TGN.webp)
- ![Cumulus Junior 300](https://media.gramino.com/medusa/b7ffaa9cbde69a386731d573ec04b3fd-01KWHVPMMF99TE8MD087WAC9V5.webp)
- ![Cumulus Junior 300](https://media.gramino.com/medusa/bfe84310b4a3501ab8d4e6b95a3c5816-01KWHVPMMMSKJS92WC1A06SFSM.webp)
- ![Cumulus Junior 300](https://media.gramino.com/medusa/31b8994bd048772a6b285a3e4f1fb2f5-01KWHVPMQJ93QBJ805494F1WKJ.jpg)

## Identifiers

- SKU: CUJU300-L
- Handle: cumulus-junior-300
- Brand: Cumulus

This product is also available as [HTML](/p/cumulus-junior-300).

Category: [Sleeping bags](/c/sleep/sleeping-bags.md) · [Sitemap](/sitemap.md)

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