This is a new set of 8 current production viton valve stem seals for the Kawasaki GPZ1100 and KZ1100. They are not factory rubber seals that have been sitting around hardening for 30 years. These are made now.....in the 21st century! Superior metal clad viton construction containing 5% Teflon for reduced friction and wear. Viton has far better resistance to high temperatures and petroleum distillates and will maintain their elasticity for many years. These are the best on the planet, satisfaction guaranteed or your money back. Please contact me if you have any questions. Thanks for looking!