Fender BXR 300C - Manual (Page 4)

(L) SPEAKER: Speaker connections are four ohms minimum.
The two jacks are wired in parallel. The BXR 300 is not
designed for speaker impedance lower than 4 ohms total.
(M) TWO SPEED FAN: The two speed fan normally runs at low
speed, and will automatically go to high speed when things
get loud. High speed operation during high level performance
is quite OK. If you suddenly reduce your level, the fan speed
(if high) may take a while to return to low (normal) speed. Do
not block air flow to the rear of the amplifier.
(N) POWER RATING: This indicates how much power the
amplifier can "draw" from the wall socket when the amplifier
is at full power (1200VA). The marking directly below
indicates what the wall socket Voltage and frequency must be.
Incorrect line voltage will damage your amplifier and VOID
THE WARRANTY!
(O) LINE CORD: The line cord should be connected to a
suitable power source, with the correct voltage and frequency,
as shown in the power rating at the amplifier rear (item N
above). if your not sure check some other piece of equipment
in your area. DO NOT ALTER THE AC PLUG.
REAR PANEL DESCRIPTIONS