The E600x range of powder extinguishers in 3,7 & 10 kilo (post '97 3, 6 & 9)has been around in one shape or form since the old E1607 back in the late 50's early 60's (a blue BC powder extinguisher of 7lb, but squeeze to stop on the nozzle rather than squeeze to start).
It was still manufactured up until a year or two ago and the long tried and tested 40 year plus design has been replaced by a Chinese squeeze grip in 4 kilo & a different design of factory sealed (still strike knob) 6 & 9 kilo model 6066 & 6099. In time I'm sure they will go all Chinese & squeeze grip using the kit made for the other London Securities firms (MK etc) by their internal 'trade' wing BWH manufacturing.
They do have a 10 year extended service interval, the primary sealed clause that's been around for decades in the BS was just for their powders, the only other manufacturer with primary sealed powders was Pyrene in the 60's with a powder filled variant of their primary sealed 3lb BCF/CBM extinguishers.
The 10 year interval is useful as the filling cost is prohibitive as special parts and adapters are required to refill it (they used CO2 instead of N2 as a propellant too). You could virtually sell a new kitemarked traditional model for the cost of taking away, filling and returning it for a customer. You could almost afford to buy a new one for the cost of a Nu Swift call out & Basic Service if you only had the one extinguisher (but with NS you would probably have at least three....).
I've never filled or extended serviced them, just put in a traditional design new or SX extinguisher in it's place.
Nu Swift have the gall to charge a couple of hundred quid for a Chinese 2 kilo Powder that will have cost them about £9.99 and you could buy as a end user for about £20 - the death of the E600x range severs NS historical ties with very solid, very long life kit.
