Each lid hole is 83mm diameter with a ring set made up of concentric rings. By fitting or removing each ring from the centre outwards reveals varying apertures 31, 43 and 59mm diameter. This allows a variety of beakers or erlenmeyer flasks to be placed directly onto the shelf in Clifton water bath. The above picture shows the SLR1-14 lid. The SLR2-14 has 6 apertures and ring sets.

The lid and rings are manufactured from stainless steel. The concentric rings provide varying hole diameters in the lid. In use the lid minimises evaporation and maintains temperature stability of the water bath when tall vessels are being heated at elevated temperatures.