Neutrik NJ3 FC-6

Made a 3.5mm to 6.35mm TRS adapter with it.
Pros:
It takes up to 8mm diameter cables without needing a different chuck and boot.
It can do only 2 poles as well, for instance a TS to RCA adapter.
The pins are positioned in a triangle, similarly to an XLR connector, which is easier to solder than tipical pin positions on TRS connectors.
Cons:
The area around the pin cups is plastic and may melt if you get too close with the iron.
The latch lock is very hard to push down - the Neutrik website says it has a locking force of more than 80 Newtons. However, taking out the spring under the red latch lock can make it a lot easier - just slide the bar to the end to lock and slide back to unlock.
The boot is a little difficult to put on without creating a gap between the housing and the connector opening. A workaround is to screw the boot halfway on, then screw the small screw into the housing and then screw the boot fully on.