Bought from here: http://www.velotechservices.co.uk/shop/vclose2.asp?prd=76574&cat=7416002009
That's the BB you need. Rotor 3D+ has a 30mm spindle and requires an outboard bearing bottom bracket to work on BSA frames.
Not sure it's the UBB as described on the rotor website though.
On a side note, the copy on VT website is rather misleading when it states
so you can use BB30 cranks in your standard Treaded (sic) Frame. BB30 road cranks cannot be made to work on BSA frames.
@Howard started
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That's the BB you need. Rotor 3D+ has a 30mm spindle and requires an outboard bearing bottom bracket to work on BSA frames.
Not sure it's the UBB as described on the rotor website though.
On a side note, the copy on VT website is rather misleading when it states