Matthew 24:21-22
"For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be. And except those days should be shortened, there should no flesh be saved: but for the elect's sake those days shall be shortened."
In context, "those days" are the days when there "shall be great tribulation", and the duration of the tribulation is a short period of time or 3 1/2 years.
Daniel 7:25
"And he shall speak great words against the most High, and shall wear out the saints of the most High, and think to change times and laws: and they shall be given into his hand until a time and times and the dividing of time."
Daniel 12:7
"And I heard the man clothed in linen, which was upon the waters of the river, when he held up his right hand and his left hand unto heaven, and sware by him that liveth for ever that it shall be for a time, times, and an half; and when he shall have accomplished to scatter the power of the holy people, all these things shall be finished."
Revelation 12:7-14
"And there was war in heaven: Michael and his angels fought against the dragon; and the dragon fought and his angels, And prevailed not; neither was their place found any more in heaven. And the great dragon was cast out, that old serpent, called the Devil, and Satan, which deceiveth the whole world: he was cast out into the earth, and his angels were cast out with him. And I heard a loud voice saying in heaven, Now is come salvation, and strength, and the kingdom of our God, and the power of his Christ: for the accuser of our brethren is cast down, which accused them before our God day and night. And they overcame him by the blood of the Lamb, and by the word of their testimony; and they loved not their lives unto the death. Therefore rejoice, ye heavens, and ye that dwell in them. Woe to the inhabiters of the earth and of the sea! for the devil is come down unto you, having great wrath, because he knoweth that he hath but a short time. And when the dragon saw that he was cast unto the earth, he persecuted the woman which brought forth the man child. And to the woman were given two wings of a great eagle, that she might fly into the wilderness, into her place, where she is nourished for a time, and times, and half a time, from the face of the serpent."
"A time (1 year), and times (2 years), and the dividing of time (1/2 a year)," and "a time (1 year), times (2 years), and an half (1/2 a year)," and "a time (1 year), and times (2 years), and half a time (1/2 a year)" are all timeframes of 3 1/2 years which is the actual duration of the coming great tribulation.
Elsewhere in the book of Revelation, it is denoted as being "a thousand two hundred and threescore days" (Revelation 12:6) or 1260 days, and as lasting "forty and two months" (Revelation 13:5), and both of these time periods are 3 1/2 years as well.
The elect are Christians.