Reflector shapes

BR40 bulb shape and size

BR40 is the large bulged-reflector flood bulb designation. Its nominal maximum diameter is 5 inches. BR40 may not fit a can designed for BR30. The base, voltage, light output, and exact overall length come from the individual lamp specification.

Representative family profile and nominal maximum diameter only. Overall length is not to scale, and the base is intentionally omitted.

Dimensions

What BR40 tells you

Shape
large bulged-reflector flood bulb
Nominal diameter
5 in (127 mm)
Typical bases
E26
Common uses
large recessed cans, high-ceiling flood lighting

The diameter is part of the naming system, not a full dimension drawing. Individual models can differ in overall length, neck profile, optics, and manufacturing tolerance. Use the maker's drawing when the fit is close.

At the fixture

Four other details to record

  1. Read the base code and voltage on the old lamp or fixture label.
  2. Compare the published maximum diameter and overall length with the available space.
  3. Record lumens, beam angle where relevant, color temperature, and dimming behavior.
  4. Look for the enclosure, location, temperature, or vibration rating required by the fixture.

Easy to miss

Notes for BR40

  • BR40 may not fit a can designed for BR30.
  • Check fixture depth and trim diameter.

Sources

Reference method

BulbMatch uses the U.S. eighth-inch naming convention as a nominal shape reference and keeps model-specific dimensions separate.