Help identifying this item ?

[flkeysdude]

This was in a toolbox that I picked up at a tag sale. The red components are molded plastic. I have absolutely no idea as to what it might be. Can anyone I.D. it for me...???

Thx !

 

[martin666]

Don't know what they're called but I've seen them on hot water heating system circulating pumps

 

[Handyfarmer]

there a coupling on a circulation pump, http://www.electricmotorwarehouse.com/couplers-2/

 

[Milton Shaw]

Coupling for circulation pump is the correct answer.

 

[flkeysdude]

Thanks guys...!!! Very much appreciated...!