The Park Tool BBT-9 is our tool of choice for installing SRAM S300 cranks. Like everything Park Tool makes, this bottom bracket tool is built to last and does the job.
From Park Tool
The BBT-9 is used to remove and install external bearing crankset bottom brackets. One end of the BBT-9 securely engages the 16 notches of the bottom bracket cups. The other end of the tool engages the 8 internal splines of the crank arm adjustment cap. The BBT-9 fits cups and lockrings with 16 external notches and an outside diameter of approximately 44mm.