2430 J

Hello,

We'd be happy to help but since the number you provided only indicated the strength of your balance spring, we'll need to see a picture of your top nylon attachment to confirm the correct replacement balance. you'll also need to remove the balance and tell us the depth of the bottom nylon fitting shown in your picture. You can measure the depth as shown in the picture below. Your depth will most likely be either 1", as shown below, or 1-1/8". Thank you!