Are b10 and b11 bulbs interchangeable

So yes, B10 and B11 (and CA10) bulbs are interchangeable as long as they all have the right fixture size to fit your wall sconces or candelabra base.

1. Is B10 bulb same as candelabra?
2. Are B11 and B12 bulbs the same?
3. How long is a B11 bulb?

Is B10 bulb same as candelabra?

B10 refers to bulb shape and means "blunt tip". They can be medium base (E26) or candelabra (E12).

Are B11 and B12 bulbs the same?

The designations B11 and B12 refer to the size of the GLOBEs, no the bases. (The number after the shape code, in this case "B", refers to the diameter of the globe in 1/8" increments. The B11 lamps are 1/8" smaller in diameter than B12 bulbs.)

How long is a B11 bulb?

For example, a C11 shaped chandelier bulb is 8/11 or (1.375) inches wide. The most common shapes can be found in the table below.
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Chandelier Light Bulb Shapes.