This is a Micro Hero ISCG05 BB adapter.
Suggested retail price 3,000 yen (tax)
Adaptor for attaching chain guides compatible with ISCG05 to frames without ISCG05 mounts.
Use it in place to secure it between the BB shell and the BB.
BLACK SPIRE does not have a line of BB mount types, so you will need to use this adapter.
Main Specifications:
Material: Aluminum alloy
Weight: Approx. 1.1 oz (30 g)
BB fixing part: 0.1 inch (2.5 mm)
Accessories: Chain Guard mounting screws M6 x 12 mm, 3 spacers (thickness 0.05 inch (1.2 mm)).