An isolation device can include a packer element that is actuated via a slip system to engage with an inner diameter of a tubing string to set the plug. The isolation device can be a frac plug. Top and bottom slip props of the slip system can be shaped such that the packer element is inhibited or prevented from engaging with an inner mandrel after the plug has been set within a wellbore. The slip props can be self-supporting; thus, the inner mandrel can be removed from the isolation device after setting and can be reused in other downhole tools. The isolation device can be used for zonal isolation to treat a zone of interest within a subterranean formation. The treatment can be a fracturing operation.