WaterBoost WB – Advant 400 slim mini3 2604B210SL

The WaterBoost WB-Advant Slim 400 Mini3 is the narrowest tank in the entire WaterBoost range — a compact, ultra-slim water boosting system for domestic properties with severely restricted access. A 400-litre WRAS-approved UK-manufactured Advant slimline tank (400mm W × 1050mm L × 1253mm H) pairs with the DAB Esybox Mini3 external variable speed pump, delivering 50 l/min at 3 bar and up to 5.5 bar maximum — with WiFi, DConnect app, Google Home and Alexa voice control.

At just 400mm wide, the vertical slimline tank passes through a standard doorway with a generous 362mm to spare — opening up loft hatches, tight cellars and utility spaces that no other tank can reach. The Esybox Mini3 sits alongside the tank for full pump accessibility, running at a quiet 45 dB(A). The tank connects directly to the mains via the pre-fitted ¾″ ball float valve, with 1.5″ outlet. All interconnecting pipework is supplied — no site assembly required.

The UK-manufactured tank carries an outstanding 10-year warranty and the DAB Esybox Mini3 a 3-year warranty. Delivery is typically 1–2 working days.