Core adjustment tool

[ppppenguin]

I suspect many of us have the traditional plastic hex ended trim tools. About 5" long with a hex section on each end. One end is backed by an enlarged round section for ease of use. The other end is backed by a reduced diameter round section so it can reach through an upper core to adjust a lower one.

I've found two in a drawer, one red, the other blue. Both from RS Components. Must be several decades old.

They still supply them: https://uk.rs-online.com/web/p/trimmer-tools/0543147