We bought our house second-hand, and the wall light switches inside it have a very recognizably Showa-era look.
For this DIY I swapped them for modern switches.
This article covers:
- The actual swap procedure
- What you need to buy
- Total cost
and a bit more.
One thing up front: this kind of work requires a Class 2 Electrician’s License in Japan.
Here’s the article on me studying for and getting that license:
For readers outside Japan: “Showa-era” refers to roughly 1926–1989; in everyday Japanese it’s also shorthand for “old-fashioned, pre-modern looking.” A “hotaru switch” (literally “firefly switch”) is a wall switch with a small indicator lamp that glows when the room light is OFF — so you can find the switch in the dark. They’re still sold today, but the body and rocker styling on the Showa version is unmistakably dated.
Before and after
Below is the original switch.
It’s a “hotaru” switch — when the room light is off, the small indicator lamp glows.
The Showa-ness is impossible to miss.
And here’s the after.
Panasonic’s “Advance Series” switches.
Reads as appropriately modern, I think.
Below: the parts and the install.
Parts
The replacement switch is from Panasonic’s “Advance Series.”
If you walk into a Japanese home center, the Panasonic switches on the shelf are still mostly the older “Wide 21” line.
To my eye even Wide 21 is starting to look dated, so I went with the cleaner Advance Series instead.
Parts and total cost
The four parts below are everything you need for one switch.
My local home center only stocked the Wide 21 line, so I ordered these online.
| Part | Model number | Approx. price |
| Hotaru switch (single-pole) | WTA5051 | ~500 yen |
| Mounting frame | WTA3710 | ~70 yen |
| Switch plate | WTA7101W | ~500 yen |
| Handle (rocker) | WTA3021W | ~300 yen |
Total parts cost was under 2,000 yen.
Amazon links for each part below ↓
Panasonic Advance Series Recessed Hotaru Switch B (single-pole) WTA5051
Panasonic Advance Series Insulating Mounting Frame for Recessed Switches WTA3710 (pack of 10)
Panasonic Advance Switch Plate (single-gang) WTA7101W
Panasonic Advance Series Switch Handle with Indicator Marking WTA3021W
A look at each part
From left to right: hotaru switch (single-pole), mounting frame, switch plate, handle.
Below — the hotaru switch (single-pole).
If a single light has to be controlled from two locations (e.g. top and bottom of a staircase), you’d need a 3-way switch instead. This light is controlled from one spot only, so a single-pole switch is fine.
The mounting frame the switch snaps into. Plastic.
The switch plate.
The trim ring around the rocker.
The handle (rocker). This is the part you actually press. (Photo shows the protective film still on the front face.)
The swap
First, obviously: kill the breaker.
※ With the breaker off, you can’t use any electrical lighting in that circuit, so you can only do this kind of work in daylight.
Confirm the room light no longer comes on, and start work.
Removing the existing switch
Pop off the front cover plate. It’s friction-fit — just pull it off by hand.
Back out the screws holding the inner plate. Two of them, top and bottom.
Then the mounting frame.
Same idea — back out the two screws holding it to the wall box.
Screws out.
Two wires (white and black) are landed on the existing switch.
These get moved over to the new switch.
Release the wires from the old switch.
The terminal is the push-in/release type — push a small flat-blade tool into the release hole next to the wire and the wire comes out.
(Aside: the tool I’m using here isn’t actually a flat-blade screwdriver — it came in the tool kit I bought when I was studying for the Class 2 Electrician’s License exam.)
Down to just bare wires sticking out of the wall.
Installing the new switch
Snap the new switch into the new mounting frame.
It’s a snap fit — just press it in.
Land the wires into the new switch.
Just push them in firmly.
Screw the loaded mounting frame back to the wall box.
Two screws — reverse of removal.
I reused the original screws from the old frame.
Snap on the handle. (It clicks in.)
Then the inner plate.
Reverse of removal — two screws (which come with the plate).
Last, snap on the outer cover plate. Just press it on, click.
Peel the protective film off the front of the handle.
Done!
Showa switch → modern switch, mission accomplished.
For peace of mind, I flipped the breaker back on and confirmed the light comes on and off normally.
Total cost was under 2,000 yen, total time under an hour.
Update
Later on, I went and did the same thing for a 2-gang switch elsewhere in the house.
Comments