What is this?

[Scott'n'Wendy]

Please look at the picture again. there is a little threaded cap that might screw on to a tire air valve. nothing like what has been listed. it is not rigid like a bar. I will need to look inside to see if there is a shaft but it would be like a rotary tool extension shaft. quite small and bendable, semi-rigid.

I looked again but see nothing like a schrader valve. I see the manual slide movement rod with a threaded nut on the end which is standard. I have two of them on my trailer. But...it is much larger than a schrader valve. If you are not referring to the rod with a nut on the end....maybe circle the exact spot you are questioning on the pic?