partnership with  Retrofit solution manufacturer logo

Retrofit solution - perfect for clean air zone compliance

Supplier and installer of the NOxBUSTER® City retrofit system

Excalibre Technologies are the proud UK partners of market-leading, Proventia Oy. The Proventia NOxBUSTER® City is a retrofit solution for ULEZ and CAZ, which enables Euro 3, 4 or 5 buses and trucks to meet Euro 6 standards.

Proventia are based in in Oulu Finland and are a leading developer and manufacturer of retrofit and OE emission control systems. The systems have full TfL and CVRAS approval ensuring compliance with the Ultra low emission zone (ULEZ) and Clean Air Zones across the UK. Over 1,000 systems have been installed across all major London bus operator

Proventia have approved systems for many vehicles including...


Engine make Engine model Displacement Vehicle examples
Cummins ISBe 4.5 4.5l ADL E200, ADL E400H, Wrightbus Streetlite
Cummins ISBe 6.7 6.7l ADL E400, Wrightbus DB300
Volvo D9B 9.4l Volvo B9TL
Volvo D5F 4.8l Volvo B5H
Mercedes-Benz OM906LA 6.4l Citaro
Mercedes-Benz OM926LA 7.2l Citaro
Mercedes-Benz OM457LA 12.0l Citaro


Engine make Engine model Displacement Vehicle examples
DAF PR265 8.2l  Temsa Safari, VDL Bova, Irizar i6

Truck (HGV)

Engine make Engine model Displacement Vehicle examples
Mercedes-Benz OM906LA 6.4l MB Atego & Axor
Mercedes-Benz OM926LA 7.2l MB Axor

Refuse Collection Vehicle (RCV)

Engine make Engine model Displacement Vehicle examples
Mercedes-Benz OM906LA 6.4l MB Econic

Key benefits of the NOxBUSTER® City retrofit system

  • High NOx reduction rates even at low exhaust temperatures (below 200°C)
  • Proven results over the Millbrook MLTB, LowCVP UK Bus (LUB), Coach (LUC), HGV and RCV Cycle
  • Proven results in PEMS tests from an independent test laboratory
  • Proven results of real city driving conditions from an independent test laboratory (WHVC cycle)
  • Proven results of real city driving conditions from independent testing laboratories
  • Operates with standard AdBlue®, no additional infrastructure required
  • Optimised urea mixing technology enable urea injection at low temperatures – no deposits
  • Advanced insulation technology maintains heat inside the system and improves SCR operation
  • Low surface temperature, no risk to other sensitive engine parts
  • Easy installation and maintenance, similar to existing AdBlue systems
  • Continuous NOx emissions and performance monitoring with a web-based Proventia PROCARE™ Drive

Installation and maintaining a retrofit solution

Excalibre Technologies has a team of highly-skilled technicians based in Rainham Essex that can install and maintain the best retrofit solution within 24-hours. After installation Excalibre Technologies provides a comprehensive service and maintenance program including DPF cleaning.

We also have a stock holding for spare parts, which ensures a fast and efficient replacement service throughout the year.

To book a retrofit  installation, please contact 01594 887414 or email us


The Proventia ProCareTMDrive is a compact device that continuously monitors the performance and operation of the system providing real time emissions data. Engine out and Tailpipe NOx are monitored and logged enabling NOx reduction to be calculated at any time. DPF back pressure is also monitored along with catalyst and DPF temperatures.

Coupled with location tracking it enables the operator or authority to monitor the performance of the vehicle. All data is available in spreadsheet format to enable whole fleet data to be collected and analysed. All software is developed in house enabling custom reporting to be offered for large fleets.

Contact us today

Contact Excalibre Technologies for a no-obligation discussion

01594 887414 |

Aftermarket Silencers

Excalibre specialize in aftermarket silencers for Euro 4 & 5 vehicles. We supply a growing range of silencers for truck and bus applications and also manufacture custom designs in house.

Emissions Control

In partnership with Synergy Catalyst and Performance Industries we supply catalytic convertors for a wide range of industrial and automotive applications. We also supply SCR catalyst and DPF’s.