3M™ Thermal Transfer Label Material 3929 is a 4.8 mil, bright silver, retro-reflective facestock with 1 mil 3M™ Acrylic Adhesive 200 on a 78 pound, clay coated kraft liner. 3M™ Thermal Transfer Label Material 3929 features a retro-reflective facestock that is designed for long range bar code scanning. The adhesive is designed for harsh environments and it is excellent for high surface energy substrates. 3M™ Thermal Transfer Label Material 3929 has good lay-flat characteristics designed for bar code labeling in warehouse environments.