These are billet main caps, originally designed for the series 3 (blacktop) zetec but they can be used on earlier models. Billet machined from a block of steel they are physically bigger and much stronger than the original main caps (especially true for the series 3) and help to eliminate crank movement, particularly crank walk which can occur at high RPM's due to the lack of a thrust bearing in the zetec's design.
They have some surface rust on them and they are unmachined so you will have to get them line bored with your block. Ideal for a high horsepower mk1 focus rs or zetec turbo build.
20160927_152033 by
Simon Oldfield, on Flickr
Photo Album:
https://www.flickr.com/gp/137039510@N06/7dptr5
£120, located in Stafford, Staffordshire if you wanted to collect