A handle mechanism 8 for a window or door, comprises a lever 10 and a rose 12. The lever 10 is journalled in the rose 12, typically by spin-riveting techniques, to allow for relative rotation between the two to operate a lock mechanism located in a window opening sash 50 to which the handle is in use attached. The handle 8 also incorporates a lock mechanism 14 that allows the lever 10 to be locked to the rose 12. A spindle 16 is located in a tapered spindle receiving cavity 18, also known as a core, of the handle 8. The spindle 16 is secured in the spindle receiving cavity 18 by means of a friction fit and also by means of a steel retaining pin 26 which is received in a semi circle clip section 28 located on an end of the spindle 16.