<s>
A	O
dual	B-Algorithm
headphone	I-Algorithm
adapter	I-Algorithm
,	O
also	O
known	O
as	O
a	O
"	O
headphone	B-Device
splitter	O
"	O
or	O
"	O
audio	B-Device
jack	I-Device
splitter	O
"	O
,	O
is	O
a	O
device	O
that	O
allows	O
two	O
headphones	B-Device
to	O
be	O
connected	O
through	O
to	O
one	O
audio	B-Device
jack	I-Device
.	O
</s>
<s>
They	O
can	O
be	O
used	O
to	O
listen	O
to	O
audio	O
through	O
multiple	O
audio	O
input	O
devices	O
,	O
such	O
as	O
headphones	B-Device
on	O
devices	O
such	O
as	O
an	O
MP3	O
player	O
,	O
CD	B-Device
player	I-Device
,	O
modern	O
Computer	O
with	O
audio-out	O
compatibility	O
(	O
such	O
as	O
a	O
headphone	B-Device
socket	O
)	O
or	O
boombox	O
.	O
</s>
<s>
Although	O
earbuds	B-Device
,	O
a	O
type	O
of	O
headphone	B-Device
design	O
,	O
can	O
be	O
shared	O
with	O
a	O
bud	O
(	O
with	O
one	O
"	O
bud	O
"	O
in	O
another	O
's	O
ear	O
)	O
,	O
a	O
dual	B-Algorithm
headphone	I-Algorithm
adapter	I-Algorithm
can	O
be	O
more	O
practical	O
.	O
</s>
<s>
Dual	B-Algorithm
headphone	I-Algorithm
adapters	I-Algorithm
can	O
be	O
purchased	O
at	O
various	O
audio	O
and	O
electronic	O
stores	O
.	O
</s>
<s>
Headphone	B-Device
adapters	O
can	O
be	O
used	O
by	O
inserting	O
a	O
3.5mm	O
Audio	B-Device
jack	I-Device
plug	I-Device
into	O
the	O
headphone	B-Device
jack	I-Device
.	O
</s>
<s>
Many	O
designs	O
of	O
headphone	B-Device
adapters	O
have	O
been	O
created	O
by	O
various	O
individuals	O
and/or	O
manufacturers	O
.	O
</s>
<s>
The	O
most	O
common	O
types	O
are	O
the	O
"	O
Y	O
"	O
design	O
,	O
adapters	O
with	O
up	O
to	O
six	O
headphone	B-Device
sockets	O
,	O
and	O
wired	O
headphone	B-Device
adapters	O
.	O
</s>
