Needed an extension for a CCM Ribcor adult stick. Went in to the store, and found that the Perani's extender fit the best. The staff had to make some slight alterations to the extender, but it fit snugly into the stick. Took the stick home, and sized it with the other stick, subsequently having to cut 2" off the extender so it is the same size as the other stick my son is playing with. Overall, the staff at Perani's was extremely helpful in finding the correct extender. Surprisingly, the adult CCM 4" extender did not work on the Ribcor. Due to it not being as straightforward as I thought it would be, before you consider buying an extender online, I'd highly recommend going to the store to have the staff find the best fit d/t possible alterations that may need to be made. Plus they were happy to do the work of putting the extender on the stick.