IS - post (or vice versa) brake adaptor

[IDB1]

Need to bolt a Grimeca front caliper to a Manitou Axel fork..

This looks like it will do the job but it states 'Avid' and there's no measurements..

http://cgi.ebay.co.uk/Avid-Disc-Brake-A ... _500wt_840

Are these things standard or application specific?

 

[IDB1]

Or this one from crc

http://www.chainreactioncycles.com/Mode ... elID=13743

 

[IDB1]

Bought the crc one . . .

Hoping I'm thinking along the right lines