Insulated Food Jar Instructions

The Insulated Food Jar has one part no other jar has: the anti-vacuum plug. Pull it before you unscrew the lid, and the jar opens on the first try. That, and everything else, is on this page.

Sizes	18 oz, 24 oz, 34 oz
Material	18/8 stainless steel, uncoated inside, with an inner copper layer
The lid	Made from recycled, food-safe plastic. It has to seal and survive being dropped.
Dishwasher	Every part goes in. No temperature limit.
Insulation	14 hours hot, 19 hours cold. No preheating needed.
In the box	Anti-vacuum plug, spork, spare seal, coconut bristle brush, cotton bag
Tested	The Insulated Food Jar is independently tested for lead under the US CPSIA. Report dated July 22, 2026.

What the anti-vacuum plug does

Hot food pulls a vacuum as it cools. The plug lets you break it.

1. Unscrew the outer lid. That is the wide top part. Set it aside, you will want it in a moment.
2. Pull the plug. You will hear the air go in. That is the vacuum letting go.
3. Unscrew the main lid and eat. It turns easily now. Without the plug it would not, and that is the whole point of it.

Before the first use

Take it apart, boil the parts for five minutes, dry them.

1. Take it apart completely. Outer lid off, main lid off, anti-vacuum plug out of the main lid.
2. Put every part in boiling water. Jar, both lids, plug and seal.
3. Wait 5 minutes. Then take everything out again.
4. Dry every part before you reassemble. The seal recess especially. A wet recess is where a leaking lid starts.

Keeping lunch hot even longer

Rinse the jar with boiling water first. That buys about another hour.

1. Boil a kettle and fill the jar. Right up. The steel needs to take the heat on, not just touch it.
2. Wait 5 minutes. Lid on while it stands.
3. Pour the water out and fill with food. Straight away, while the steel is still warm.

Cleaning it

Every part goes in the dishwasher. Rinse the coarse bits off first.

1. Rinse the coarse food off in the sink. Two reasons: your dishwasher filter stays clear, and the jar actually comes out clean.
2. Take it apart and load every piece. Jar, outer lid, main lid, plug, seal, spork. All of it goes in.
3. Dry the seal recess afterwards. Then reassemble. A dry recess is what keeps the lid sealing.

Two things people miss

The outer lid is a bowl, and the bag has a pocket for the spork.

1. Turn the outer lid upside down. That is your bowl. Eat the soup out of the jar and the bread out of the lid.
2. Look inside the transport bag. There is a small compartment sewn in. The spork lives there and stops rattling around your backpack.

Washing the cotton bag

Hand wash only, in warm water at around 86 °F.

1. Hand wash in warm water. Around 86 °F. Hotter water shrinks the cotton.
2. Air dry it. No dryer.

When something wears out

A lost plug means you buy a plug, not a new jar. Every wearing part on this jar is sold on its own.

• Seal set
• Anti-vacuum plug
• Outer lid
• Screw cap
• Spork
• Cleaning brush
• Cotton bag
• All spare parts

Questions we get asked

Why will my food jar not open?

A vacuum formed as the hot food cooled. Unscrew the outer lid, pull the anti-vacuum plug, and the main lid turns freely. That is exactly what the plug is there for.

Is the Insulated Food Jar dishwasher safe?

Yes, every part of it. Jar, outer lid, main lid, plug, seal and spork all go in, at any temperature. Rinse coarse food off in the sink first.

Is the lid plastic?

Yes. The lid is made from recycled, food-safe plastic. That is deliberate: it has to seal, and it has to survive being dropped. The body your food sits in is uncoated 18/8 stainless steel.

My lunch was not hot after 14 hours. What went wrong?

Three things decide it. Fill the jar right to the top, close it, and leave it closed until you eat. If lunch is late, rinse the jar with boiling water for five minutes first — that adds about an hour.

Can I put it in the microwave?

No. Stainless steel does not belong in a microwave, and the vacuum wall does not either. Heat the food first, then fill the jar.

Does it carry soup without leaking?

Yes, that is what it is built for. The thicker solid-material seal and the precise thread hold liquid. That is why soup belongs in the jar, not in a lunch box.