If you’ve got a Back-to-wall toilet and Cistern and want to replace your worn-out Toilet Seat , then you’ll probably be looking for a special type of toilet seat fixing. No more seats sliding around! The fixing’s name is a Well-Nut . They are specially designed to be used with blind-holes in toilet pans. Not many places sell these special toilet seat fixings, so you’ve found the right place! We keep pairs of these in stock and can ship them by Royal Mail to you. Technical Dimensions: Expanding well nuts 11mm - 23mm Length 35mm How It Works:The tightening of the screw, threaded in the brass nut, causes the insert sleeve to expand, therefore the diameter is adjustable. Guarantee Length: 1 Years