CPR instruction Sign with 1/4 inch lettering (Heavy Duty White Aluminum) This sign is a lightweight, durable, weatherproof outdoor sign. Choose either Plastic or Aluminum! Signs are digitally printed with UV resistant inks to prevent fading. All four corners of our plastic signs are pre-drilled with 1/4 inch grommets pre-installed for easy mounting. Recommended for mounting on walls or other flat surface mounting.