Dark Gray Fabric Kupu 10 Smoke Alarm by Jalo Helsinki. The Jalo Helsinki smoke detector Kupu 10 is a renewed version of the original Kupu. The Kupu 10 still looks as stylish and cool as the original Kupu, but this Kupu 10 has an upgrade. Namely a strong built-in lithium battery that lasts up to 10 years. Hence the name Kupu 10, because the battery of this smoke detector guarantees a service life of 10 years. That is also the legal lifetime of a smoke detector. So you no longer have to think about replacing the batteries of the smoke detector. They look stylish and you no longer have to hang them in a corner, but you can just view them.