The original replacement grips for the Stairmaster 4000PT were available as a 'shrink to fit' design. The grips were sealed in a pack with additives that when exposed to air, made the grips shrink or tighten. These grips are no longer available. Sportsmith does not offer a replacement grip for the Stairmaster 4000PT.
The grip size that is needed for the 4000PT stepper is one that fits a 1 1/2" diameter. The grip should be an open-ended grip to allow for it to slide onto the handlebar. The length of the grip can be any length that suits the owner or user's desire.