Rodent Skin Buttons are used for externalizing a catheter or for an attachment of a spring tether to the animal as an alternative to the harness or jacket. The advantage of a skin button is lower chance of infection, secure catheter anchoring and the ability to keep the catheter away from the animal. The polyethylene button center has an inner diameter of 0.123" which makes a perfect friction fit with a standard stainless steel spring tether with an OD of 0.124".