Sphinx of black quartz, judge my vow. (29 letters)

Waltz, bad nymph, for quick jigs vex. (28 letters)

A perfect pangram contains every letter of the alphabet only once and can be considered an anagram of the alphabet. The only perfect pangrams of the English alphabet that are known use abbreviations or other non-dictionary words, such as “Mr Jock, TV quiz PhD, bags few lynx”, or use words so obscure that the phrase is hard to understand, such as “Cwm fjord-bank glyphs vext quiz”, in which cwm is a loan word from the Welsh language meaning an amphitheatre-like glaciated depression, vext is an uncommon way to spell vexed, and quiz is used in an archaic sense to mean a puzzling or eccentric person. It means that symbols in the bowl-like depression on the edge of a long steep sea inlet confused an eccentric person.

https://en.wikipedia.org/wiki/Pangram?useskin=vector