In various examples, an apparatus is configured for subcutaneously inserting an implantable device within a patient. The apparatus includes a dilator portion including a dilator including a dilator length. The dilator portion is configured to separate tissue to create a subcutaneous pocket within the patient sized and shaped to accommodate an implantable device within the subcutaneous pocket. A sheath portion includes a sheath sized and shaped to accommodate the dilator within a sheath lumen. The sheath is configured to accommodate an antenna of the implantable device with the dilator removed from within the sheath. The sheath includes a sheath length that is at least substantially as long as an antenna length. The sheath is configured to separate to allow removal of the sheath around the implantable device to remove the sheath from and leave the implantable device within the subcutaneous pocket within the patient.
