A cikin masana’antar hasken wuta, muna amfani da lambar sauƙi don nau’ikan kwan fitila daban-daban da siffar kwan fitila.

Misali A60 yana nufin kwan fitila mai siffar A, kuma diamita nasa shine 60mm.

G120 yana nufin kwan fitila mai siffar G, diamita gare shi shine 120mm.