Thought I'd chime in here. I'm actually pretty familiar with both of these test strips and had similar results with them. Did you go off Amazon to buy these? I'm guessing so. I purchased 5 or 10 of each off Amazon due to the reviews.

Moral of the story though, I routinely got lighter test lines on the brand you have in the left in that picture, as it appears you did as well. I did multiple tests on the same sample with both brands, and that brand routinely was lighter, however, neither ever showed a fail.

Both your pics though are a pass regardless :thumbsup:
halo09 Reviewed by halo09 on . Different test different results I have used several brands of THC strip tests. On one recent batch the second line is very faint even when testing a known negative and even tap water while another brand test used at the same time has a nice bold line. The test with the very faint line seems to be very sensitive to even the slightest amount of THC. After getting repeated negative results, then taking as little as one or tow puffs - the line becomes almost invisible. At the same time the other brand shows a clear second line. Rating: 5