I am clueless on the border issue, but I suppose that was already answered
.
You should be aware of each states' definition of "paraphernalia", which you can find by looking up their Controlled Substance Act at
http://www..gov (example [url="http://www.wa.gov"]www.wa.gov www.ca.gov ). Not to say it would be used (it hasn't with the Marquis), but I know CAs'(and many others'), for instance, states:
"As used in this chapter, "drug paraphernalia" means all equipment, products, and materials of any kind which are used, intended for use, or designed for use in planting, propagating, cultivating, growing, harvesting, manufacturing, compounding, converting, producing, processing, preparing,
testing, analyzing, packaging, repackaging, storing, containing, concealing, injecting, ingesting, inhaling, or otherwise introducing into the human body a controlled substance. It includes, but is not limited to:"
"(4) Testing equipment used, intended for use, or designed for use in identifying or in analyzing the strength, effectiveness, or purity of controlled substances;"
"(c) In determining whether an object is drug paraphernalia, a
court or other authority may consider, in addition to all other
logically relevant factors, the following:"
"(2) Instructions, oral or written, provided with the object
concerning its use for ingesting, inhaling, or otherwise introducing
a controlled substance into the human body.
(3) Descriptive materials accompanying the object which explain or
depict its use."
Health and Safety Code section 11014.5
In otherwords, just be responsible & prepared.