Just got back from the land of the BIG and this was one of the stuff hand carried home - The TiAL Sport 3" V-band clamp part number VC355. TiAL does not sell direct hence I got the clamp from one of their distributors - Road Race Engineering or RRE. RRE have been extremely helpful in expediting the delivery of the v-band clamp to my hotel even though the part was out of stock and had to be ordered. Just look for Lydia Welch @ RRE.
The TiAL VC355 is one of the V-band clamps recommended for use to mate the EFR6258 turbine with the GCG downpipe flange which I'm currently having a replica CNC machined from a block of stainless steel with approval from GCG :) Pictures below of the TiAL VC355 stainless steel V-band clamps. There are two of them as the other is meant for Bro who wants to replace his ancient T25 with the EFR6258 on a Super Satria SOHC. That's like carrying a rocket launcher to a gunfight!
Locking bolt on the clamp
Super close up