identify your lightbulb > bulb identification key

STEP 3: Un-tipped, Inside Frosted Bulbs
[Bulb is entirely frosted on the inside]

Select the option most resembling your bulb from the drop-down menu to proceed to the next step. Please consult "option descriptions" for detailed info.

[The drop-down menu can be re-set by refreshing your browser window.]

FULL OPTION DESCRIPTIONS / IMAGE GLOSSARY: [Option titles are also linked to proceed to the next step.]

Note: To see the filament of an inside frosted lamp, or a soft white lamp, shine a flashlight through the bulb from the back and look for the shadow of the filament.

OPTION A: Bulb is entirely frosted inside, with a smooth surface on the outside of the bulb.  Bulb should have a pearl-like color in appearance.  This is an Inside Frosted Light Bulb, which was introduced in 1925.  Filament is made of either a single or double coiled tungsten filament and mounted [see A91 or see A118] (i.e., either horizontally or vertically).  Single-coiled inside frosted light bulbs were manufactured starting in 1925.  Double-coiled were introduced in 1935.  If bulb shows two filaments and/or has three different wattages etched on top of bulb, bulb is a three-way inside frosted light bulb introduced in 1933 [see Figure 209t?]. key no. [540a]

Pathway History:
2 || Untipped-Bulb-Options

3 || Untipped-Inside-Frosted

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