AP / EASTERN markets and sells their catalytic converters under both AP EXHAUST and EASTERN CATALYTIC. The product inside the box is the same, no matter what brand name appears on the box.
AP / EASTERN 71421 Specifications
Air Tube Qty
1
Body Length (IN)
12"
Catalyst Type
Standard
Inlet Gasket Qty
None
Inlet Hardware
None
Inlet Type A
2.25" ID
O2 Sensor Ports
None
Outlet Gasket Qty
None
Outlet Hardware
None
Outlet Type A
2.25" ID
Overall Length (IN)
16"
Shape
Oval
Test Weight
5.9 / 6000
Type
Federal / EPA Universal
E.P.A. Compliant
Eastern Catalytic Features:
Proprietary NANO technology chemistry yields highly efficient loadings for lower cost and better converter efficiency.
Full top and bottom heat shields on most converters.
High flow design retains maximum engine output and maximizes catalytic efficiency.
Selecting the correct Universal Converter
Determine what type and size body you need a) round unit or oval unit b) long or short body
Establish the gross vehicle weight (usually on the inside of the left front door jam)
Check to see if the replacement unit needs an air tube or O2 sensor fittings (all Eastern Catalytic Converter air tubes are capped)
Verify the correct position of the inlet and outlet
Measure the diameter of the O/E pipe to ensure that you have the right size inlet and outlet
Fix the problem that caused the original converter to fail before installing the new converter
Have You Fixed the Problem that Caused your OEM Converter to Fail?
Catalytic Converters are designed to last the life of your vehicle – they do not fail on their own. It is important to fix the source of the problem before replacing your OEM converter. There are three major reasons a converter fails:
OVERHEATED / MELTED
Often caused by unburned fuel entering the converter from a faulty:
Spark Plug
Exhaust Valve
Oxygen Sensor
Fuel Injector
Burned Converter
CATALYST POISONING
Often caused by exposure to emissions substances from:
Leaky Cylinder Head Gasket
Silicone-Based Sealant
Improper Fuel (E85, Diesel)
Worn Piston Ring / Valve Seal
Oil Fouled Converter
STRUCTURAL DAMAGE
Often caused by road debris, corrosion or other conditions such as:
Have You Fixed the Problem that Caused your OEM Converter to Fail?
Helpful Tools: 
Videos
Additional Resources