This Quartz Tube is 646mm long x 22mm OD with a Dome end. Standard Quartz Tube Compatible with the Greenway GW GAUV-10S UV system.
Quartz tubes can be used in many makes and models so long as the overall length and width matches the UV make and model you have. 95% of UV manufacturers use the 22mm OD width on the quartz and only the Davey Steriflo use the 25mm OD quartz.
You will also need to know if your Quartz Tube is open both ends (the hole goes right through) or closed one end.