Manual Focus Gear

[CrippledSandwich]

Anyone know what this is used for? i was looking through warehouse express dot com and found this:

(http://www.warehouseexpress.com/product/default.aspx?sku=1015041)

also why the high price tag it doesn't look much

 

[Lufbrarunner]

Used with an underwater housing I believe. Smaller market = expensive part.

 

[Carl V]

According to Olympus, it goes onto a 35mm macro lens when using the camera in a housing unit.