Light bulb shape reference

Bulb shape codes describe the physical envelope of the glass — separate from the base type. A bulb is identified by both shape and base (e.g., A19/E26).

• A19 — standard household bulb shape
• A21 — larger household bulb shape
• BR30 — bulged reflector flood
• PAR38 — parabolic aluminized reflector spotlight
• MR16 — multifaceted reflector
• G25 — globe decorative shape
• T8 — tubular fluorescent/LED shape

See also: A19 vs A21 comparison