Hastings 3.78125 Standard Bore, 8-Cylinder Ring Set with 5/64" Top Ring, 5/64" Second Ring, and a First Oil Ring is 3/16".
This Hastings 8-Cylinder Ring Set has a top ring manufactured from grey iron with triple chrome ring surface treatment and a second ring manufactured from grey iron with a phosphate ring surface treatment. The 1st oil control ring is manufactured of steel rail/stainless expansion with a chrome rail ring surface treatment.

Application Summary:

Year Make/Model
1957 DeSoto Firedome
1957 DeSoto Fireflite
Attributes
1st Oil Groove 3/16
1st Oil Ring Material STEEL RAIL/STAINLESS EXP
2nd Groove 5/64
2nd Ring Surface Treatment PHOSPHATE
Alternate Part Number 2C682
California Proposition 65 No
Engborein 3.78125
Hazardous Material Code N
Life Cycle Status Code Available to Order
NAFTA Preference Criterion Code B
SDR Required Flag N
Top Groove 5/64
Top Ring Surface Treatment TRIPLE CHROME
GTIN 00075538036340