Telescopic post designed to be positioned in an opening, such as a door- or window-type opening delimited by a casement, or of the type delimited by adjacent walls so as to form a post of a frame arranged so as to receive a sealing element, for example a tarpaulin, said telescopic post comprising: - a first, outer profile comprising a front wall, a rear wall and two connecting walls (32, 33), each of the walls having an inner face and an outer face, said first profile having an open portion forming a cavity of a first, essentially U-shaped channel, said front wall comprising a longitudinal orifice forming an opening of said first channel, of which the adjacent portions are formed by two inner lips (21, 21'), each extending from one of the connecting walls (32, 33), and - a second, inner profile comprising a front wall, a rear wall and two connecting walls (32', 33'), each of the walls having an inner face and an outer face, said outer face of one of said connecting walls of said second profile being provided with a wiper over at least part of its length, said second profile having an open portion forming a cavity of a second, essentially U-shaped channel, said front wall comprising a longitudinal orifice forming an opening (35") of said second channel, of which the adjacent portions are formed by two inner lips (9, 9'), each extending from one of the connecting walls (32', 33'), said first and second profiles being concentric and arranged so as to engage by sliding, and said telescopic post being characterized in that said first, outer profile comprises, on said inner face of a wall facing one of said connecting walls of said inner profile, a gutter formed in a wall thickness and arranged so as to receive said wiper located on said second, inner profile when said first and second profiles are arranged so as to engage by sliding. - a first, outer profile comprising a front wall, a rear wall and two connecting walls (32, 33), each of the walls having an inner face and an outer face, said first profile having an open portion forming a cavity of a first, essentially U-shaped channel, said front wall comprising a longitudinal orifice forming an opening of said first channel, of which the adjacent portions are formed by two inner lips (21, 21'), each extending from one of the connecting walls (32, 33), and - a second, inner profile comprising a front wall, a rear wall and two connecting walls (32', 33'), each of the walls having an inner face and an outer face, said outer face of one of said connecting walls of said second profile being provided with a wiper over at least part of its length, said second profile having an open portion forming a cavity of a second, essentially U-shaped channel, said front wall comprising a longitudinal orifice forming an opening (35") of said second channel, of which the adjacent portions are formed by two inner lips (9, 9'), each extending from one of the connecting walls (32', 33'), said first and second profiles being concentric and arranged so as to engage by sliding, and said telescopic post being characterized in that said first, outer profile comprises, on said inner face of a wall facing one of said connecting walls of said inner profile, a gutter formed in a wall thickness and arranged so as to receive said wiper located on said second, inner profile when said first and second profiles are arranged so as to engage by sliding.