This is a small block short water pump pulley. Sorry if I'm wrong about some of the details. I'm not an expert in these parts and clear information is hard to get. 

I tried to show the dimensions in the pictures. A little less than 6 5/8" total diameter. A little under 3" total height. 5/8" pilot hole diameter. 1.75" diagonally between the center of the bolt holes. It weighs 1 lbs 8 oz.

I'm not sure of the new/used condition. It came from a shop that closed around 2017 and recently cleared out inventory. This pulley has some wear, but I'm not sure if it's new with general shelf wear, if it was temporarily installed, or if it was used for a while on an engine. 

The pulley in the pictures is the one you will receive. 

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