0515-431477 retail Solid and constructive since 1972! As the operator of 28 KARWEI & 7 GAMMA DIY stores , the Posthuma Group is a national player and therefore also an important franchisee of lntergamma BV in Leusden. Intergamma BV operates the KARWEI & GAMMA formulas . About the Posthuma Group The Posthuma Groep BV originated from a construction company that was founded in 1972 by Douwe Posthuma. In 1982 the first DIY store was opened in Scharnegoutum. This “Bouwmarkt 82″ is the predecessor of the current KARWEI in Sneek. read more © Posthuma Groep BV | Disclaimer | Site map | Privacy statement | Cookie settings | We use cookies on this website to make it easier to use the website, to improve performance and user experience and to increase the relevance of the offer on this website and on websites of third parties. If you click on agree, you give permission for this. Click on settings to indicate which cookies you accept. InstitutionsAccept