You'll need one 9V battery for the urine level indicator (not supplied). Everything else — solids bin, urine bottle, DC-DC charger, a compostable liner and a high-barrier liner sample, battery box, and bag pusher — comes in the box. The wall charger is optional and sold separately.

Compostable liners are black, made from industrially compostable material. High-barrier liners are white, with extra durability and odour protection. Whichever you choose, use the S1 app to tell the toilet which material it's sealing.

No — it has a wide, stable base and most people use it freestanding. If you'd prefer it not to move, there are four eyelets in the base for screwing it to the floor. If you don't fix it down, just make sure it's stowed so it can't slide or tip while travelling.

The app is required to tell the S1 which liner material you're using, and it's how you install firmware updates. It's also used to pair with the toilet during setup.

150 kg / 330 lb, on a stable, level surface.

Yes, it's fine to leave it in place, full or part full, while travelling.

The bags can hold liquid waste, but you can add a coagulant powder to turn excess liquid into a gel and reduce the risk of spills.

At room temperature, generally a few hours up to 3 days depending on conditions, contents, and liner material. In hotter conditions, try to dispose of bags within 48 hours — sooner is always better.

Each liner is marked near the end of the roll. When you see the end-of-liner mark, feed and remove the remaining liner and install a fresh roll. If you're switching liner materials, update the setting in the app.

No — the sealing mechanism draws air through the solids bin via a fan, and a bag in the bin blocks that airflow and can damage the fan. The only exception is manual mode, where the sealing mechanism has been removed entirely (see the troubleshooting section below).

Check the battery isn't flat — the unit runs off the battery, not the charger directly, so a very low battery can stop it powering on even while plugged in. Charge fully and try again. If it still won't power on, check the sealing mechanism's connector to the battery box.

Check nothing is obstructing the solids bin below the liner. When installing or replacing liner, make sure the fold lines sit concentric around the sealing mechanism opening — misalignment can cause feed issues.

Remove the bag liner and let the unit air-dry completely for 24 hours before using it again. Avoid exposing the S1 to direct water streams, always sit down while using it, and avoid very humid/wet environments.

Yes, both are user-replaceable. Switch the S1 off first. The 9V battery (urine sensor) is behind its own cover. The lithium battery pack is inside the battery box behind a removable cover — fit only a genuine CompoCloset lithium pack.