Bergquist Self-Adhesive Thermal Interface Sheet, 0.125in Thick, 2.7W/m·K, Gap Pad 2500, 200 x 100mm

Electrical insulators and thermal conductors
Adapted for electrical insulation and as thermal joints on assemblies of components where the height varies
The material has excellent elasticity
The thicknesses available (1, 2 & 3.2 mm) mean that GAP Pads can be used when the texture of the surface varies
The Ultra Soft range has the same characteristics but is softer and more malleable