Norimitsu of the Eikyo to Kyotoku eras is known from four dated works: a of Eikyo 2 (1430), of Eikyo 10 (1438) and Bun'an 2 (1445), and a of Kyotoku 2 (1453) that was designated at the 43rd session and raised to the following year. The published sources trace the name back to a first Norimitsu said to have been a pupil of Nagamitsu, whose dated Kagen 3 survives. They record the sequence in full: 「銘鑑では、これを初代とし、二代を延文頃、三代が応永で家助の子とし、四代が永享頃、五代が長禄・寛正頃で、以後室町末期まで名跡の継承があったことを記している」 (the count that smith as the first generation, a second around Enbun, a third in Oei as the son of Iesuke, a fourth around Eikyo, and a fifth around Choroku and Kansho, with the name carried on to the end of the period).
Within that sequence the published sources place the present smith as the fourth. They note that works up to the Oei era at the start of the period are very few; one paper puts it that the line lapsed and was revived in the period. By contrast, the maker of the Kyotoku is held to be the fourth generation of the , with comparatively many surviving works, and famed alongside Sukemitsu as one of the two pillars of Eikyo . The paper on the Bun'an gives his common name: 「この文安の則光はその四代目にあたり、五郎左衛門を名のっている」.
His share a recognisable manner. On the Kyotoku the is finely forged, with minute , fine and a clear . The is based on open at the base, mixed with angular , and pointed elements. and enter freely, the is slightly tight with , and there are scattered . The runs in irregular, small and round on the and pointed on the , with fine . The published sources find the features of Norimitsu well displayed here. They call it a masterpiece among his works, more varied than usual in the rise and fall of the temper and in its and .
The Bun'an shows the same pattern: a in the , open at the base with a feeling, and , and a that runs in and turns back pointed. Its paper reads this as the inheritance of the Oei manner, the bright and clear. The Eikyo 10 , long even after shortening, has a flowing with that tends to stand, and a of mixed with and , deep in . The published sources write 「この太刀は姿・作柄にいまなお応永備前の風を保ち、地刃の出来が見事である」 (in shape and workmanship this still keeps the manner of Oei , and its and are splendid).
The Eikyo 2 is a different register. It is , without and somewhat thick, with Sanskrit characters carved on both faces. Over a well-forged with runs a in with a little . The published sources call it one of his representative works and find in it the features of work of the period.
The Kyotoku comes with a contemporary black-lacquered , an iron chain fitting, a silver brocade bag woven with large chrysanthemums on a dark blue field, and a vermilion-lacquered box. The published sources describe the mounting as a valuable example of an archaic military black-lacquered that carries the style. They consider the bag a very rare Japanese silver brocade datable to the period.