New English Made Triumph Progressive Outer Fork Springs. If you are looking for a more positive front suspension action installing progressive fork springs will do just that. Made in England to replace Triumph part number 97-1891 and H1891. Measures 10″ in length, outer diameter measures 2″ and inner diameter measures 1 5/8″. Suited for Triumph twins (Bonneville, T120, Tiger, TR6, 6T & Thunderbird, TR6SS & TR6SR) from 1964-1970. Also fits all Triumph 350 & 500 Unit Twins (3TA, 5TA, T90, T100SS, Tiger, T100SR, Daytona, T100T & T100R) from 1965-1974. Please refer to your parts catalog for proper fitment.*****Please read the entire listing to ensure the best fitment.*****Made in EnglandO.E.M Part number is 97-1891 or H-1819