Gasket Retainer with spikes, Curved for Left and Right Sides, These are used on the Dr. Oligo synthesizers 96 - 768. These use 6-32 screws. These are wider than the original ones. These can be used to replace the original curved gasket retainers however you will need 6-32 screws and you will need to drill out the existing 4-40 hoes and tap them to 6-32 holes. The straight gasket retainers with this same design are PN: 262-104370. The advantages of these new type gasket retainers is that they hold the gasket in better and they make a better seal without need for silicon sealer when installing them.