Although many of the features of the B model made it a rather innovative design, it was clearly a complete service in itself. The BA model, Kilta (Guild), on the other hand, was a series of monochromatic articles that could be used for a wide range of different purposes and which could, for instance, be used together with other services. Kilta represented a concession by the management of the Wärtsilä Group to Kaj Franck, giving him the freedom to experiment with new ideas and to create a design that differed from the traditional dinner service.

In its early form Kilta comprised only a few different items: a couple of shallow plates, a deep soup or dessert bowl, a rectangular platter, a square vegetable dish, a lidded jug, different sized bowls, lidded bowls, a coffee cup and saucer, and a creamer and sugar bowl, the only difference being that the handle was omitted or a spout added. All three pieces had the same lid.

Each article could be used for a wide range of purposes, e.g. as dishes for preparing, serving or storing food. The service was made of glazed earthenware and all the pieces, apart from the early version of the long rectangular mould, were heatproof. An attempt was also made to keep the costs of making Kilta down by turning it out with one firing only.

The shape of Kilta was also an innovation since Franck used pure geometric forms. It was the first time that square and rectangular dishes had ever been produced at Arabia, for instance. The fact that Erik Johansson and Gösta Lindfors, Arabia's plaster model makers, also participated in designing Kilta made the work much easier. This resulted in the model designing department being able to have its own plaster model makers.

Kilta was originally designed without any decoration and was produced only in plain white, black, green, blue or yellow. A brown series was also made in trial runs for a short time. Decorated versions were made to some extent later.
In 1953, Kilta was put on show in Arabia's exhibitions at home and abroad where it immediately attracted a lot of interest. The Danish newspaper, Socialdemokraten, even talked about a revolution in the kitchen. Despite the positive reviews in the press, Kilta did not initially sell very well in Finland since it differed rather radically from the familiar type of services.

At the same time Arabia started its first extensive information and advertising campaigns to get consumers interested in the new models. The factory attempted to influence both sales staff and custormes through advertisements, holding training and demonstration sessions and setting up sales rooms. Arabia's information bulletin "Ceramics and Glass", distributed to shops and firms in the field, also first came out in 1953.

Kilta gradually became a sales success. The range of Kilta articles was greatly expanded and it finally attained the status of a classic, remaining in production until 1975. It was a service that was greatly missed when its manufacture was finally discontinued, Kilta became Arabia's most popular model with sales totalling over 20 million pieces in a period lasting for 20 years.