Ensure good thermal contact in the hardest materials

METER recommends using thermal grease when using RK-3, TR-3, and TR-4 needles in solid materials like rock and concrete. This allows for better thermal contact with harder materials that will not conform to the needle as easily as a medium like soil. Additional thermal grease can be ordered directly from METER.

Pilot holes can be drilled into hard materials, like rock, using an appropriately sized drill bit. For concrete and other materials that may be too brittle (such as concrete) or too malleable (such as firm soils and insulation) for a drilled pilot hole, we recommend using a pilot pin.