These work great for small slings. At Shane's Spiders, we usually use them for slings of almost everything. Great size for those little 1/2-1" slings to start out in.
These vials will not come with any ventilation. The sides can be drilled out with a small drill or holes can be poked/Punched/Drilled in the lid rather easily.
Here at Shane's spiders we often use 20 drams for extra small slings (like dwarf species) and sometimes don't use ventilation at all for those slings because they are so small. We simply open the enclosures at least 1 time per week, and we are sure to start with the desired moisture when we set up, and then we DON'T ADD ANY WATER during our routine maintenance. The most common size we use is 40 drams which house about 95% of all our slings. We usually drill several holes (approximately 0.050" diameter) in the sides of the vials for ventilation and they will contain most slings over .25" DLS just fine. Occasionally we also use the 50 drams for arboreals, or fossorials, especially the zippy ones that you want a little extra room with.
Sizing Guide:
The first dimension will be the approximate Outside diameter and the second will be the approximate over all height. (ex Diameter" x Height")
20 Dram - 2.1875" x 1.1875"
40 Dram - 2.1875" x 3.4375"
50 Dram - 2.1875" x 4.375"
