Actually leak proof lunch boxes

[MojoMoon]

I have a couple of Sistema quaddies to take my lunch to work in and they leak a bit

I take salad and dressing in a little bottle but there is still some liquid in a salad from the chopped up veg and it always leaks out

I cycle or walk so it gets bounced around a bit

What actually is leak proof? I think it probably needs to have a silicon seal or something similar, right?

I use a clip top with silicone seal tub from Ikea for my overnight oats, haven't had any milk leaks yet. Might be worth a shot?

Lock'n'lock are the best in my experience (I work in a kitchenware shop).

Definitely lock and lock boxes.

I’ve sent dd1’s lunch in them for years, and never a single leak (and she’s not gentle with her lunchbox, it gets chucked around all over the place).

Another vote for lock and lock, there are knockoffs around (eg the ikea ones), which don't leak but mostly break sooner.