Kashi Scientific Self Standing Centrifuge Tubes 50mL, [50 Pack] Plastic Test Tube with Screw Caps, 50mL Sterile Test Tubes with Lids, 50 mL Skirted Tubes with Printed Graduation and Write-on Spot

TLDR: High-quality tubes, No off-putting smell, Airtight seal, Good for coffee bean storage in the freezer The tubes came well packaged and did not have any plastic or an off-putting smell. After washing each tube with warm water and dish soap, I used the tubes to store single-dosed coffee beans and have not had any issues with air leaking or caps getting stuck after being in the freezer for prolonged periods. The tubes create a good enough airtight seal where no coffee smell leaks out. The pour-overs and espressos I made have proven that the tubes do their job at preserving the coffee beans well. It seems to be a cost-effective option rather than getting tubes with one-way valves that can break.

Not sterile. The outer and inner bags of this product was punctured in multiple places, making the product no longer sterile. Do not purchase if you require sterile tubes.

Atendeu ao meu propósito que era acondicionar grãos de café no freezer. Gostaria que o plástico fosse mais robusto.

False branding. Sold by Kashi Scientific from the US. However, the packaging says Ningbo Medical Instruments, made in China.

I use these centrifuge tubes to collect biological sample with. The caps and tubes are good quality. They work well for both liquid and solid collection vessels. They are affordable and for my purposes, they are exactly what i need. I will buy more.