This is a leg attachment for the Ironmaster Super Bench. I'm not sure if it would fit other benches. It's barely used, just like new.
I'm not sure what you'd pay if you bought it directly from Ironmaster, but it's for sale in Canada for $180 here: https://www.fitnessequipmentottawa.ca/en/product/superbench-attachments_2/superbench-attachments--ironmaster-leg-developper-attch-