Without cap: as the "pros".

I was surprised to unpack.
This gourd has no "cap".
It is similar to that seen on the Tour de France.
Just press the bottle to mouth
(So-so: it's my son who made bike bcp who told me !!
Hence the "squeeze" in the title. I had seen po! ;) ...)

So, I feared a leak, which never came.
It is waterproof. Light and well large (650ml).
Happens in every classic bottle cage.
Its transparent side allows to see the level constantly.
That too I find convenient. It avoids ending up dry.

After a clear water rinse, no plastic taste like some.
Would recommend to do ... As the pros!