ZLK 18mm Green Round Bowl (Green)

14mm-18mm Glass Bushing Adapter

Glass-100 18.8 mm Glass Bowl Male Glass Accessories

12-162 SCIENTIFIC GLASS 18MM BY 18MM DOWNSTEM STANDARD DIFFUSER CLEAR ASSORTED SIZES 3"

SCIENTIFIC SUPPLIES, 12-289 BOWL STANDARD AMBER 18MM

Polykarmatic Glass Daisy Screens for Pipes(100 pcs w/ BPA free breakage-proof container)

MMKER Handcrafted Glass items, replace bowl, male adapter, 14mm / 18mm (18mm, Blue)