Here is the flag of Sklené, Pardubice region (Svitavy district) in Czechia.
It was approved 5 October 2004 and published in Petr Exner's Vexillological
Lexicon of Czech municipal flags 2004.
Description: red, with three white, hoisttriangles, each charged with
a red flower; in center a yellow glass chalice, flanked by a white key,
bit down, and a white sword, pointing downwards.
Sklené was formerly part of Sudetenland (kreis Zwittau = Svitavy) and
named Glaselsdorf. At this
webpage is the old coat of arms: gules a chalice of natural colors
with two branches vert connected below by a ribbon or. I assume it is now
different, but the (canting) glass stayed.
Jarig Bakker, 3 Nov 2007