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← MU12
MU12 — Candidate to replace following?
Rectifier — B4
⚠ Safety
Top 10 Picks
V41
drop-in
4V
✓ Close
IW3
drop-in
4V
✓ Close
Your Tube
Base:
B4
Heater:
4V / 2.5A
Type:
rectifier
Pinout (B4)
a1
h
h
a2
Candidates to replace (2)
Fit:
Drop-in
2
Adapter
0
Status:
✓ Close
2
2 shown
▣ Compact
⚙ Thresholds filter
4V Heater
(2 candidates)
Tube
Status ↑
Pa
Ah
Fit
IW3
✓ Close
—
1
drop-in
V41
✓ Close
—
0.5
drop-in
Generated 2026-04-09
Status legend →
User Guide →
target +
0
selected
pick 1+ to compare
select 1+ candidate to compare