c1960 Mercian, quite original

[bikeworkshop]

https://ebay.us/m/45kLyW

But what's the funny plate on the rear rack for?

 

[PeterPerfect]

https://ebay.us/m/45kLyW
View attachment 998679
But what's the funny plate on the rear rack for?

To fit a rear light. Some rear lights had a metal clamp with a bevelled fitting, 2 screws so you could adjust the angle.

 

[bikeworkshop]

Of course!
Using the bracket designed to clamp around the seatstay, which is no good if you have panniers.

 

[biggs682]

https://ebay.us/m/45kLyW
View attachment 998679
But what's the funny plate on the rear rack for?

Very nice

 

[Laldi]

That's a lovely bit of history, hope it goes to a good home.