![](https://coimages.sciencemuseumgroup.org.uk/35/918/large_thumbnail_1993_0722.jpg)
Indicator, two button
![Indicator, two button, Sax's patent](https://coimages.sciencemuseumgroup.org.uk/472/301/medium_smg00305526.jpg)
Indicator, two button, Sax's patent, marked 'SAX'S PATENT NO 8844 June 1888'.
Details
- Category:
- Telecommunications
- Object Number:
- 1914-801
- type:
- indicator
- credit:
- General Post Office. Telecommunications
Indicator, two button, Sax's patent, marked 'SAX'S PATENT NO 8844 June 1888'.