Excalibre Technologies Ltd - Retrofit exhaust specialists, DPF cleaning providers and technology experts in exhaust aftertreatment solutions. Excalibre are the approved partner and distributor for Proventia Oy retrofit exhaust systems for Bus, Coach and HGV applications, installing in excess of 1,700 systems nationwide. Operating in the UK with two Sales and Service locations in Gloucestershire and in Essex , Excalibre promises and delivers solutions with a fast , reliable and efficient service.