no Ring. The need Ring: http://www.bullbikes.com/es/home/2532-plato-sram-qx1.html

The mountain crank ROTOR CNC aluminum and triple casting. Perfect weight- rigidity - resistance
Some cranks with 30mm axle , powered UBB30 making them compatible with virtually all bicycle market .
features:
- Cranks mountain for 1 plate with BCD 76x4
- Axle 30mm UBB30 technology.
- Forging CNC
- TDS Technology
- Factor - Q : 163
- Linea chain : 56
- Maximum lightness of aluminum : 511g for the 170mm REX 2.1 version (without BB no plates ) .
- Certified to EN 14781 Test
- Oversize aluminum axle (30mm ) .
- Compatible with dishes Rotor Q -rings BCD 76x4 and / or round plates if they meet the standard BCD 76x4


• 30mm Axle Aluminum UBB ; support BSA , ITA , BB86 , BB30 , BB30 PF , and pictures BB386 Evo