The gear from your original distributor must be re-used.

Will work for piont distributors, will not work with pulse distributors.
Brand new distributor with several different advance curves. Your original ignition coil can be used with this new 123 distributor, as long as it is in good shape.
Keep in mind that this new item will give a stronger spark, which might cause worn cables and coils to fail.

How to connect your 123 distributor