Thinkster of Steel Straw Bottle
Steel-bodied toddler straw bottle with a soft silicone straw - but the collar and valve the water passes through are polypropylene.
Plastic-free verdict: Minimal plastic contact
The bottle base is ultra-polished 304 stainless steel and the straw is medical-grade silicone, but the cap, collar, and spill-resistant valve assembly are polypropylene, and water passes through that plastic valve on its way up the straw. So while the body is steel and the mouth touches silicone, plastic is still in the water path. It is less plastic than a fully plastic toddler bottle, but not silicone-only. Best for the 16-48 month range where a soft, spill-resistant silicone straw matters.
Verification: Manufacturer confirmed · reviewed 2026-07-05
What it's made of
| Part | Material | Food contact |
|---|---|---|
| bottle body ultra-polished 304 (18/8) stainless steel | Stainless Steel (304 / 18-8) | Yes |
| straw extra-soft medical-grade silicone straw with cross-cut anti-spill tip | Silicone | Yes |
| cap / collar / valve BPA/BPS/phthalate-free polypropylene; water passes through the valve assembly | Polypropylene (PP, | Yes |
Thinkbaby's stainless-steel toddler straw bottle. It is a genuinely steel bottle (304 body) with a soft silicone straw, marketed hard on being free of BPA, BPS, phthalates, PVC, and similar. The catch is the closure: the swivel cap, collar, and leak-reducing valve are polypropylene, and the water travels through that plastic before reaching the silicone straw. Practical and durable for little kids, but not a zero-plastic-contact option.
Pros
- Steel (304) body with a soft, replaceable medical-grade silicone straw
- Spill-resistant cross-cut straw and swivel cap for toddlers
- Free of BPA, BPS, phthalates, PVC, and similar plasticizers
Cons
- Polypropylene collar/valve is in the water path - not plastic-free or silicone-only
- Silicone straws need replacing every few months
- Single-wall (non-insulated); handles/base add plastic parts on some versions
Notes
- Sizes: 9oz Thinkster of Steel; replacement silicone straws sold in 3-packs
- All non-steel closure parts stated by brand as polypropylene; straw is medical-grade silicone
- Water-through-valve contact with polypropylene is inferred from the closure design (community/vendor-reported), not from an explicit teardown
Categories: Kids Water Bottles
Sources
Every material claim above is backed by these. This is the scattered info we centralized.
- manufacturer https://thinksun.com/products/thinkbaby-of-steel-85 base is ultra-polished 304 stainless steel; straw is medical-grade silicone; all plastic components are polypropylene
- review https://carobambino.com/products/stainless-steel-thinkster-straw-bottle retailer detail confirming steel base, polypropylene cap/collar, and food-grade silicone straw