Old house wiring -- old-style switch loops; solution using in-box module

[rcjordan]

Sonoff zbmini in the fixture turns a spst switch into a toggling device without repurposing the switch legs.

Sonoff ZBMINI

Using this following wiring diagram, the zbmini combined with a SPST switch overcomes the 'No Neutral' problem in current US wiring methods. The SPST switch now toggles the light. (C4 / Generic Zigbee Switch)