This is a drop in replacement for the EK1-0540 feathering shaft that is used with the stock Belt CP head/blade holders (i.e. the plastic ones). Slightly stronger and stainless design make these an economical choice over the Esky part. These parts are designed to bend on blade strike but will survive lighter knocks better than the Esky stock parts. Please note these are now sold individually rather than in 5 packs.