These high quality mop frames boast many unique design features such as the permanent curve set in the frame (edges pointing downwards) which ensures there is equal pressure across the mop and a low profile design which makes it easy to mop under doors. Also, being aluminium they have the ability to conform well to uneven floors. The heavy duty swivel is designed to have a more restricted movement in one direction to make it easier to control if mopping walls and ceilings. The unique Velcro fastener strips have an amazing grip onto the mop backing yet it will not prematurely wear the backing like traditional Velcro or collect dirt/lint. Replacement strips and end caps are available.