Hello. On July 20th 2019 I collected this fossil from Ramanessin Brook in Colts Neck, NJ. The dimensions are 2 1/4 inches long, 1 1/8 inch wide at the top, tapering to 1/2 inch at the bottom. There is a notch a half inch from the bottom on one side. If anyone knows what it is please let me know. Thank you.