PTFE Insulated Test Point Jacks & Accessories Keystone Electronics PTFE Insulated Terminals, Pins, Turrets, and Test Point Jacks feature a space saving design for high density packaging, as well as outstanding electrical, mechanical, thermal, and chemical properties. The Keystone PTFE Insulated Terminals, Pins, Turrets, and Test Point Jacks are RoHS compliant and provide greater pull-out strength and high torque resistance. These components are ideal for high quality terminal and connector applications.