frame extend through said window frame and are screwed within lugs 74 see fig3 and 4 integrally molded with the buck frame 10 at the appropriate locations in the jambs 16 ramps 42 effect a better seal when the gazed sashes 56 are closed because of the greater compression of band 66 at its ends the buck frame 10 is inserted within the wall forms for pouring concrete in the proper orientation as indicated by the marking 76 and arrows 78 as shown in fig4 if necessary braces can be inserted within the buck frame opening to further resist weight of the freshly poured concrete however this has generally not been found necessary after the buck frame is embedded in the concrete and the concrete is cured and the wall forms removed the window frame lintel part 46 together with the band 66 of compressible material are releasably fitted within the buck frame then the sill part 48 is fitted and by raising the lintel part 46 as shown by arrow 80 in fig1 against the bias of the compressible band 66 it is possible to insert and fit the jamb parts 50 the glass panes g g 39 with or without a sash 56 can be then installed within the guiding tracks 58 of the window frame 44 by lifting the lintel part 46 whenever a glass pane 54 and or a sash 56 or a part of the window frame 44 is broken it is easy to remove the glass panes.