Spawn bottle 12 bottles no filter ②

These are empty mushroom substrate bottles that were used for raising stag beetles, including *Dorcus hopei binodulosus*, at home with children.
The bottles have been rinsed with water, but please understand that there may be some residue remaining.

800 cc, 12 bottles

There are signs of larvae chewing and dirt on the filters, so please consider these as used items and purchase only if you understand this.
The items will be shipped in recycled cardboard boxes.

Please note that I am currently on a work assignment away from home, so shipping will occur when I return home. Please allow for some time before shipment.