With this CNC manufactured aluminum boom, it is possible to drive conventional derailleurs with an 11-40, 11-42 or 11-46 wide range cassette. The adapter is simply mounted between derailleur hanger and rear derailleur and so puts the rear derailleur further down. This prevents that the upper pulleys come too close to the largest pinion of the cassettes. The extended link better guides the chain over the entire sprocket set and wraps around the sprockets to a much greater extent, increasing the shifting precision.

Compatibility rear derailleur / cassettes:

Shimano SLX RD-M7000-10-SGS / 11-46 Cassettes ( 10-speed )
Shimano DEORE RD-M6000-SGS / 11-46 Cassettes ( 10-speed )
Shimano DEORE RD-M615-SGS / 11-42 / 11-46 Cassettes ( 10-speed )
Shimano ACERA RD-M390-SGS / 11-40 Cassettes (9x)
Shimano TY RD-TX800 / 11-40 Cassettes (8x)
SRAM GX 2015 (Type 2.1) LD / 11-46 Cassettes ( 10-speed )
SRAM X9 2015 (Type 2.1) MD / 11-46 Cassettes ( 10-speed )
SRAM X5 / 11-42 and 11-46 cassettes ( 10-speed )