Marcy Sensor Pads are made using a special, fingerprint-resistant silicone. The patented clamshell molds produce a consistent shape and thicker pad, making for a better fit and contact to glass. Helps you to avoid air pockets. Protective package makes pads easy to remove and apply, free from contaminants. No hassles with bags or hard- to-remove liners. User-friendly, cost-effective, consistent quality. Now NAGS listed. All Marcy Sensor Pads (MSP parts) are made of user-friendly SILICONE (not red-liner acrylic).