How easy would it be to extend the shower-head hose? Is it a standard-size that I could find an extension for easily?

I bought 3/8th by 1/2 in diameter tubing from Menards. Swapped the hardware. And now I have a 15ft hose for my shower head. Was not difficult to swap.

can you turn the water flow off at the shower head?

No the water has to be continuous running for the heater to work.

Coleman is avoiding the GPM on this unit. my question is what else are they not telling.

I sent mine back. Coleman, flow rate was sufficient, and is largely dependent on the input pressure. YOU are the igniter for the Coleman. I chose instead to return my Coleman, and purchased a Triton on-demand. The Triton is self igniting (D cell batts) and has an internal flow sensor. So, add batteries, hook it up to a water and propane source, and you have instant hot water when you turn the valve.

Manufacturer	Coleman
Part number	2000026562
Item Weight	227 g
Product Dimensions	55.25 x 27.31 x 43.82 cm; 226.8 g
Item model number	2000026562
Color	Red
Style	portable
Material	Plastic
Power source type	Liquid Propane
Voltage	12 Volts
Wattage	1.2E+2
Item Package Quantity	1
Number Of Pieces	1
Flow Rate	3 Liters Per Second
Maximum Pressure	8 Bars
Plug Profile	Wall
Special Features	Shower Head with 6-foot Non-Kinking Silicone Hose
Batteries Included?	Yes
Batteries Required?	No

ColemanHot Water on Demand H2Oasis Portable Water Heater

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