what are some established businesses here?
RS systeme GmbH, Motorola GmbH, Jack Wolfskin, DG-Verlag (distribution and logistics), and a few others.
Idstein
Among the bigger businesses in town are, for instance, RS systeme GmbH, Motorola GmbH, Jack Wolfskin, DG-Verlag (distribution and logistics), E. Schmitz Trading & Technical Services GmbH, Black & Decker/ELU-Gruppe (Elektrowerkzeuge) and Thermoplast + Apparatebau GmbH (thermoplastic injection-moulded articles).

what is unionskirche, idstein? It is the active Protestant parish church of Idstein. where is the latter mentioned place? It is a town in the Rheingau-Taunus-Kreis of Darmstadt in Hesse, Germany.
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Idstein [SEP] Established businesses
Roughly 200 small and midsize businesses, mainly in crafts and retail sales, characterize Idstein's business life; four out of every five have fewer than ten employees. Among the bigger businesses in town are, for instance, RS systeme GmbH, Motorola GmbH, Jack Wolfskin, DG-Verlag (distribution and logistics), E. Schmitz Trading & Technical Services GmbH, Black & Decker/ELU-Gruppe (Elektrowerkzeuge) and Thermoplast + Apparatebau GmbH (thermoplastic injection-moulded articles). Another important employer and factor in the economy is the "Landeswohlfahrtsverband Hessen" (Hesse State Welfare Federation) with its SPZ (paediatric centre) Kalmenhof, an institution aiding youths and people with handicaps.