737 QRH checklist symbol
The older checklists had this particular symbol "< >" when a circuit breaker had to be pulled by the flight crew during a non-normal situatuon.This symbol was after the name of the checklist.The last few revisions have it for a number of checklists where there is no circuit breaker to be pulled(Mainly in a number of checklists in the hydraulics,flight controls and landing gear).