This is a stand / tray to hold the parts of the API Ammonia NH3 / NH4Test Kit.

Both solution have a slot to hold them. The comparison card can be added to the slot in the back for testing, or can be left there. The other three hole allow for the filled test tube to be held while you place while you add the test solutions. This hole can also be used for comparing your sample to the test card. The other two holes are for drying the test tube and cap after testing and cleaning are completed.

KingRoon KP3S

Doesn't Matter

No

25% or more to add mass

There may be some threading between the drying post and the card holder. Strong threading may break the post off. Use a filament that you have good control over the threading to minimize this issue.