In Sweden, the 16 A is generally used for stoves and to some extent for other heating devices in kitchens. In the Netherlands, Perilex is also used to connect fans with wired speed control (Switched L2 and L3 pins), but fans may not use three phase power Sweden: Semko 17 plugs Semko 17 were 3/4-pin 3-phase connectors, with (4-pin) or without (3-pin) a neutral connector. Earth were provided via the shield. The connectors were available in different sizes, 16 A with rounded corners; 25 A and 63 A were rectangular. These connectors were used mainly in industrial and agricultural installations. Manufacturing and selling of Semko-17 connectors with metal shells was prohibited in 1989. A few years later manufacturing and selling of all Semko-17 connectors were prohibited. Existing connectors may be used but not by any employee (prohibited by "Arbetsmiljöverket"). The reason for the prohibition is that Semko-17 had several safety issues. The ground connection can become oxidized and when the shells are made of metal any ground fault goes right through the hands of a person connecting/disconnecting a male and a female cable connector (unless the person wears insulating gloves). Incorrect use of the ground connector as a neutral was not uncommon. Perhaps the worst issue is that in some connectors the ground screw could rust so severely that the ground wire comes loose and in the worst case make contact with a line (phase) wire nearby. Switzerland: SN 441011 The Swiss standard SN 441011 (until 2019 SN SEV 1011) Plugs and socket-outlets for household and similar purposes. defines a hierarchical system of plugs and sockets including both single and three phase connectors. Sockets will accept plugs with the same or fewer number of pins and the same or lower ratings. Single phase Swiss plugs and sockets are described in the main article SN 441011. The type 15 plug and socket has 3 round pins of 4 mm diameter, plus 2 flat pins (for L2 and L3). It is designed for three phase applications and is rated at 10 A, 250 V/440 V. The socket will also accept types 11 and 12 plugs, and the Europlug. The type 25 plug and socket has 3 rectangular pins, 4 mm x 5 mm, plus 2 flat pins (for L2 and L3). It is designed for three phase applications and is rated at 16 A, 250 V/440 V. The socket will accept types