The TMM4 from Rogers Corporation is a Laminate with Dk (Dielectric Constant) 5, Df (Dissipation Factor) 0.002, Td 425 °C, Thickness Inches 0.015" (0.381mm), 0.020" (0.508mm), 0.025" (0.635mm), 0.030" (0.762mm), 0.050" (1.270mm), 0.060" (1.524mm), 0.075" (1.905mm), 0.100" (2.540mm), 0.125" (3.175mm), 0.150" (3.810mm), 0.200" (5.080mm), 0.250" (6.350mm), 0.275" (6.985mm), 0.300" (7.620mm), 0.5, Thermal Coeffecient 16 ppm/°C. More details for TMM4 can be seen below.