Henkel Loctite Corp. has introduced two highly flexible cyanoacrylate adhesives for applications that must withstand vibration, impact and fatigue loads. Loctite 4851 and Loctite 4861 instant adhesives deliver excellent long-term performance on flexible substrates such as tubing, o-rings, rubber, paper, leather and fabric. Both flexible cyanoacrylate products are clear and formulated to provide reduced hardness and improved thermocycling resistance. These adhesives will bond a wide range of metal, plastic, or elastomeric materials, and are particularly suited for use on flexible, porous, or absorbent substrates. Typical applications include the bonding and sealing of medical devices, the assembly of loudspeaker components and the general purpose bonding of flexible and/or delicate substrates. Both products are pending ISO 10993 biocompatibility compliance for use in medical device applications. Loctite 4851 instant adhesive is a medium viscosity, single component adhesive for general purpose bonding. Loctite 4861 instant adhesive is a high viscosity, single component adhesive ideal for bonding porous and absorbent materials.