Hastings 6.25" Standard Bore, Single Cylinder Ring Set with 1/8" Top Ring, 3/32" Second Ring and a First Oil Ring is 1/4".
This Hastings SIngle Cylinder Ring Set has a top ring manufactured from grey iron with chrome ring surface treatment, a second ring manufactured from grey iron with chrome ring surface treatment. The 1st oil control ring is manufactured of grey iron with a chrome ring surface treatment.

Application Summary:

Year Make/Model
1991 Thomas Bus
Attributes
1st Oil Groove 1/4
1st Oil Ring Material GREY IRON
1st Oil Ring Surface Treatment CHROME
2nd Groove 3/32
2nd Ring Surface Treatment CHROME
California Proposition 65 No
Engborein 6.25
Hazardous Material Code N
Life Cycle Status Code Available to Order
NAFTA Preference Criterion Code B
SDR Required Flag N
Top Groove 1/8
Top Ring Surface Treatment CHROME
GTIN 00075538043690