TUBEOFILE
Search
Compare
FAQ
Tube+
Sign In
Sign In
☰
Loading...
← V41
Rolling Candidates to replace V41
Rectifier — DHT — B4
⚠ Safety
Top 10 Picks
MU12
drop-in
4V
✓ Close
IW3
drop-in
4V
✓ Close
AZ31
adapter
4V
✓ Close
RGN1064
adapter
4V
✓ Close
UU4
adapter
4V
✓ Close
IW4/350
adapter
4V
✓ Close
RGN2304
adapter
4V
✓ Close
UU5
adapter
4V
✓ Safe
UU6
adapter
4V
✓ Safe
Rolling Candidates (64)
i
Heater:
2.5V
4
4V
9
●
5V
25
6.3V
17
7.5V
1
10V
1
12.6V
3
16.8V
1
18.9V
1
22.4V
1
25V
1
show all (11)
Fit:
Drop-in
2
Adapter
7
Status:
✓ Close
34
✓ Safe
30
9 shown (target 4V only)
▣ Compact
⚙ Thresholds filter
4V Heater
(9 candidates)
Tube
Status ↑
Pa
Ah
Fit
IW3
✓ Close
—
1
drop-in
MU12
✓ Close
—
2.5
drop-in
AZ31
✓ Close
—
1.9
adapter
IW4/350
✓ Close
—
2
adapter
RGN1064
✓ Close
—
1
adapter
RGN2304
✓ Close
—
1.1
adapter
UU4
✓ Close
—
2.3
adapter
UU5
✓ Safe
—
2.3
adapter
UU6
✓ Safe
—
1.4
adapter
Generated 2026-04-09
Status legend →
User Guide →
Rolling FAQ →
target +
0
selected
pick 1+ to compare
select 1+ candidate to compare