Replacement part suitable for the following makes and models;
Stihl 
021, 023, 025, BT120, BT121, FC44, FR350, FR450, FR480, FS23, FS24, FS25, FS26, FS36, FS40, FS44, FS94, FS120, FS200, FS250, FS300, FS350, FS380, FS400, FS450, FS480, FS500, FS550, FT250, HL91, HL92, HL94, HS46, HS56, KA120, KA250, KM94, MS150, MS181, MS192, MS193, MS201, MS210, MS211, MS230, MS241, MS250, MS261, MS271, MS291, SP92, SP200, SP400, SP450, SP451, SP481
Echo
CS300, CS301, CS305, CS306, CS310, CS340, CS341, CS370, CS400, CS3000, CS3400
Flymo
XLH420, XLH550
Makita
EK6100
McCulloch
CS350, CS390, CS410, CS450, Gladiator 550, Pro-Mac 10-42, 10-46, 10-51, Mac Cat 838, MH542P, MT270X, MT280, MT300X, MT302X, MT320, MT330, Titanium 555, Tivoli 63, Tivoli 65, Virginia 542
Partner
HG22, HG63, HG65, HG550, P4616, PH61, 4200, 4600, 4700, 4900, 5000, 5200, 5300
Ryobi
274-3, 275-1, 2800R, 280r, 310BVR, 320BVR, 364, 410R
Stihl
021, 023, 025, BT120, BT121, FC44, FR350, FR450, FR480, FS36, FS40, FS44, FS120, FS200, FS250, FS300, FS400, FS450, FS480, FS500, FS550, HT250, MS150, MS181, MS192, MS193, MS210, MS211, MS230, MS250, SP200, SP400, SP450
Walbro
WT-23A, WYJ-33, WYJ-34, WYJ-45, WYJ-92, WYJ-94, WYJ-86
D 21mm, twin pipe fitting, approx. H 33mm