4pcs Matte Silver Wheel Hub Inserts Mercedes Benz A0004003800 9283

It’s very straightforward to measure your center caps size without any expert help:

Outside Diameter (OD)

The outside diameter is the total width of the center cap across the front face.

How to measure:

• Place the center cap face-up on a flat surface

• Measure straight across the widest point from edge to edge

This measurement confirms whether the cap can pass through the wheel opening.

Inside Diameter (ID)

The inside diameter is the opening on the back of the center cap. This measurement is critical for proper fitment.

How to measure:

• Turn the center cap over

• Measure from one inner edge to the opposite inner edge

If the inside diameter is too small, the cap will not install. If it is too large, the cap may not hold securely.

Depth (Height)

Depth refers to how far the center cap extends inward once installed.

How to measure:

• Place the center cap face-down

• Measure from the mounting lip to the deepest point of the cap

This measurement ensures proper clearance with the wheel hub.

Measurement Guidelines

• Always remove the center cap before measuring

• Measure the cap itself, not the wheel

• Take each measurement more than once to verify accuracy

• Use millimeters instead of inches whenever possible

Why Accurate Measurements Matter

Incorrectly sized center caps can:

• Fail to install properly

• Fall out during driving

• Sit unevenly in the wheel

• Cause damage to mounting clips

Accurate measurements help ensure a secure fit and a clean, finished appearance.

Additional Tip

If the original center cap is missing, measuring the wheel opening may provide an estimate. However, the most reliable fitment comes from measuring an existing cap whenever possible.