Split impeller

[Slick Fork]

DSC01101.jpg by CDeeth, on Flickr

Here's a shot of it out of water, the connection to the skimmer body is metric, a 1" female is too big and a 3/4" female is too small. The connection is about 5 and 1/4" up the body of the skimmer.

Reading now that the "IN" series by vertex is discontinued in favour of their upcoming omega series, doesn't bode well for replacement part hunting.