Heres what I did and my results.
First I filled the QF bottle with cold tap water then took the heating pad and taped (or use a rubber band) it to the side of the bottle without the temp. strip.

Put it under my nuts and in about 1 hour it was @ 92 degrees.As time went on the heating pad made it warmer till it peaked at 98-100 degrees.
It held this temp for 10 hours.

After that I poured it out and refilled it with cold tap water again.(even tho the pad had stoped heating I left it taped to the bottle)
This time I went out in 30 degree weather and put it on my defroster on my dash of my car with the heat pad down as the heat from the defroster heated the pad and bottle it took 20 mins to reach 95 degrees.

put it under my nuts again for 30 mins with the heating pad on the side of my whitey tightys.
After I looked it had held a temp. of 94 degrees.

In a pinch stall for time get a hot coffee always good for a quick heat.
(for this you may want to put it in a zip lock baggie to save the temp strip.

So I must say QF 4.0 works if you hand it to the collector @ 90-100 degrees.

P.S.I used the premixed QuickFix.
If anyone else tryed Quick Fix and passed or failed let me know.(Please)
So far It worked for me.But due to random drug testing at my work.I will not know for sure till after that test.But I put it to the test and all looks good so far.
You can also buy hand warmers at WalMart 6 for $2.
These work a bit better
Clawed Cooper Reviewed by Clawed Cooper on . For those that have used quick fix... How hot does the heating pad get? Will it make it too hot or does it keep it in the desired range? I had planned on crotching it with the heating pad on the bottle...is that even necessary? Thanks again! Rating: 5