Store at room temperature. Keep containers closed to prevent contamination. With proper storage, resin and hardeners should remain usable for many years. After a long storage, verify the metering accuracy of the pumps. Mix a small test batch to assure proper curing.
Over time, 105 Resin will thicken slightly and will therefore require extra care when mixing. Repeated freeze/thaw cycles during storage may cause crystallization of 105 Resin. Warm the resin to 125°F and stir to dissolve crystals.
Hardeners may darken with age, but physical properties are not affected by color. If clear finishing, be aware of possible color shift if very old and new hardeners are used on the same project.