This 7mm chain adjuster nut fits:

(Not in original packaging)

1979 & 1980 CR125R

1978 thru 1980 CR250R

1971 thru 1973 CB350F Four cyl.

1970 thru 1972 SL350K Motosport

1974 CB360

1974 CB360G

1975 & 1976 CB360T

1976 & 1977 CJ360T

1974 & 1975 CL360 Scrambler

1978 CB400A Hondamatic

1975 thru 1977 CB400F Super Sport

1980 & 1981 CB400T Hawk

1978 & 1979 CB400TI Hawk

1978 & 1979 CB400TII Hawk

1979 thru 1981 CM400A Hondamatic

1981 CM400C Custom

1980 & 1981 CM400E

1979 thru 1981 CM400T

1966 thru 1968 CB450 Black Bomber

1968 thru 1974 CB450K Super Sport

1982 thru 1986 CB450SC Nighthawk

1982 CB450T

1968 thru 1975 CL450 / CL450K Scrambler

1982 & 1983 CM450A Hondamatic

1982 CM450C Custom

1982 & 1983 CM450E

1975 & 1976 CB500T Twin cyl.

1975 thru 1977 CB550F Super Sport 

If you rebuild or restore any type of vehicle you know how important it is to use genuine / original factory / or high quality aftermarket parts. A repair or restoration project is intended to return that motorcycle to as close to original as possible, all the way down to last nut, bolt, cotter pin, cable or 7mm chain adjuster nut.

If there's even a chance you'll need this/these replacement part(s) in the future you'd better get them NOW!. Keep this in mind,  replacement parts are always good to have. When you decide to sell your Honda, including a few extra replacement parts always sweetens the deal for both buyer and seller.