Hi,selling 6 boat windows with aluminium frames heavy duty windows.. the 2 big windows have slide windows both windows slide as should..... measurements are from left to right if you in large the picture will show a,d,c,b,,,in picture. A,window is 23 x 18 inches. D,windows is x2 off is 33 1/2 x 18 1/2. C,window is 18 1/2 x 16 1/2.... B, window is x2 of 25 1/2 x 18 1/2....the measurements are from the out side of the frames..buy to collect or can post at buys cost..any more info please ring or email thank you....