Review on BASIN Large Capacity Silicone Under Sink Mat - Holds Over 2 Gallons - Waterproof Kitchen Cabinet Liner - Under Sink Tray for Drips, Leaks, Spills - Easy to Clean by Antoine Collins

A special adhesive is required to bond silicone to silicone. 100% silicone sealant will not stick to the silicone sheet. Revain sells a special glue, but it's very expensive. My solution was to cut the silicone around the cleaning nipple and fold the edges. Then I cut the plastic glass in half and stick it on the fitting. Drops from above are localized. The total volume of the mat holds more than 2 gallons, but be aware that the water volume will decrease significantly when there are many containers on the mat. If I just had a copper tube down the middle I would make a much smaller hole and then cut through the mat, put some under the slot to raise that area and also put some over the slot.