With five hole sizes ranging from 3.5 mm to 14.5 mm, this holder accommodates various thermometers including liquid in glass, electronic with probe, and bimetal with probe.Stainless steel, spring loaded clip attaches securely to laboratory containers, shelves up to 3/8” thick, and moreRubber bumpers on clip prevent scratchingDurable polyurethane foam provides secure grip to keep thermometers in place