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FR-4 (or FR4) is a NEMA grade designation for glass-reinforced epoxy laminate material. FR-4 is a composite material composed of woven fiberglass cloth with an epoxy resin binder that is flame resistant (self-extinguishing).

"FR" stands for "flame retardant", and does not denote that the material complies with the standard UL94V-0 unless testing is performed to UL 94, Vertical Flame testing in Section 8 at a compliant lab. The designation FR-4 was created by NEMA in 1968.

FR-4 glass epoxy is a popular and versatile high-pressure thermoset plastic laminate grade with good strength to weight ratios. With near zero water absorption, FR-4 is most commonly used as an electrical insulator possessing considerable mechanical strength. The material is known to retain its high mechanical values and electrical insulating qualities in both dry and humid conditions. These attributes, along with good fabrication characteristics, lend utility to this grade for a wide variety of electrical and mechanical applications.

Grade designations for glass epoxy laminates are: G-10, G-11, FR-4, FR-5 and FR-6. Of these, FR-4 is the grade most widely in use today. G-10, the predecessor to FR-4, lacks FR-4's self-extinguishing flammability characteristics. Hence, FR-4 has sincewhen? replaced G-10 in most applications.
Fenhar FR-4 epoxy resin systems typically employ bromine, a halogen, to facilitate flame-resistant properties in FR-4 glass epoxy laminates. Some applications where thermal destruction of the material is a desirable traitcitation needed will still use G-10 non flame resistant.
FR-4 by fenharxz.com August 7, 2024
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The FR4WG 

The act of eating shit out of a dudes ass while fondling one dudes balls while beating the other dude off into a glass cup and the drinking the shit down his own throat with the cum.
its close to the sleepy white boy The FR4WG
The FR4WG by Zombie ranark July 3, 2010

gzhtb .7uüuzih6d fxcv<>‡ÙÅ∂‚fr4gt65

When pp go ouchie :,,,(
Oh no mah weewee…

I‘M GONNA gzhtb .7uüuzih6d fxcv<>‡ÙÅ∂‚fr4gt65!
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A seemingly endless debate with a idiot
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Texas is categorized as a swing state in presidential elections, but has voted for Republicans more times than for Democrats in recent history. As such, as demographics change political alignments, some Democrats believe that Texas will vote blue, or Democratic, due to their Hispanic and African American voters, who often align themselves with the Democratic Party's liberal wing.

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Democrat 1: You've been saying that since 2008 though.
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briefcake 

"Did you check out the briefcake in courtroom C?"
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Brought to public attention by Bob Woodward and Carl Bernstein in the book on the fall of Richard Nixon, All The President’s Men, ratfucker was Nixon’s term for a political operative who sows chaos among opponents; an agent provocateur. It is thought to have originated among campus political rivalries at USC, and seems to have some usage in the US military.
Along with Nixon’s other ratfuckers, Roger Stone caused fights at otherwise peaceful Democratic Party protests to generate a false narrative that the Democrats were violent and dangerous.
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countrypolitan 

Term used to describe someone who is a mix of both rural (country) and urban (metropolitan) lifestyles/upbringings. He/she is typically equally comfortable in both settings and is able to seamlessly slip back and forth between the two, appreciating the characteristics of each.
That ol' gal of mine drives the 12 lane freeway during the week and a John Deere on the weekends. She likes opra and the Grand Ol' Opry. I love them countrypolitan women.
countrypolitan by MOChick November 7, 2006
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Witch Bath 

A bath consisting of a variety of slats, oils, soaps or any other added ingredients such as fruits, milks, herbs or any other spices for health or beautifying benifits.
She brought home alot of stuff and took it to the bathroom. She must be taking a witch bath.
Witch Bath by carnieboy30 October 26, 2020
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