This sintered activated carbon stick filter (Ф37.5×75 mm) is a coconut-shell carbon block with built-in ion-exchange resin, designed to reduce chlorine, odours, colour, heavy metals and scale in drinking water. It suits point-of-use purifiers, RO systems (as CTO or T33 stages), direct-drinking dispensers, refrigerator water filters and commercial coffee machines. Zanxis manufactures it in Zhongshan, Guangdong, China, with full OEM/ODM customisation and CNAS-accredited lab reports available on request.
| Item | Detail |
|---|---|
| Product name | Carbon block water filter / CTO filter for water purifiers and refrigerators |
| Core filtration material | High-iodine-value coconut shell activated carbon + food-grade ion-exchange resin |
| Core performance | Softens water and helps prevent scaling; strong adsorption of residual chlorine (bleach); removes off-colours and odours; intercepts harmful heavy metals such as lead and mercury |
| Precision and service life | Uniform microporous structure, high initial flow, high filtration accuracy and no black powder release; large saturated adsorption capacity for long service life |
| Regular sizes (OD × length, mm) | Ф60×130 / Ф62×240 / Ф37.5×75 / Ф38×57 / Ф40×195 / Ф51×127 / Ф32×126 / Ф32×106 |
| Main end applications | Household RO purifiers (pre- or post-carbon stages), direct-drinking dispensers, side-by-side refrigerator water filters, commercial coffee machines |
| Customisation | Full OEM/ODM support. Length, diameter and inner/outer diameter ratios can be tooled to match equipment needs; end-cap welding customisation supported |
| Quality system | Production base certified to ISO 9001 and IATF 16949; filter media meet strict drinking-water safety standards; quality control backed by a CNAS-accredited testing centre |
Before selecting this carbon stick, confirm the parameters that directly affect fit and performance. The regular size is Ф37.5×75 mm, but the table lists other diameters and lengths for reference; actual dimensions must match your housing and end-cap design. Ask for the iodine value of the coconut shell carbon and the proportion of ion-exchange resin, because these determine chlorine reduction and softening capacity. Filtration accuracy is described as high with no black powder release; request the test report for the specific batch if this is critical. Flow rate and pressure drop are not fixed for all applications; provide your system's operating flow and pressure so Zanxis can recommend the right grade. Expected service life depends on water quality and daily volume; the general guidance for this product is 3–6 months, but confirm with your own water analysis. Finally, confirm end-cap type, welding requirements and packaging to avoid rework.
Zanxis recommends a structured sample sign-off before mass production. The typical sequence is:
This workflow reduces the risk of dimensional mismatch or performance shortfall at mass-production stage.
The filter is made from high-iodine-value coconut shell activated carbon combined with food-grade ion-exchange resin, formed into a rigid stick through a 100% flexible moulding process. This construction gives a uniform microporous structure that supports high initial flow, high filtration accuracy and no black powder release. The ion-exchange resin contributes softening action and helps prevent scaling, while the carbon adsorbs residual chlorine, off-colours, off-odours and organic compounds; the block also intercepts harmful heavy metals such as lead and mercury. Typical installations include household reverse-osmosis purifiers (as a pre-carbon CTO or post-carbon T33 stage), direct-drinking dispensers, side-by-side refrigerator water filters and commercial coffee machines. Because the stick can be produced in many diameters and lengths, it can be matched to existing housings without changing the overall system design.
Zanxis operates a self-built laboratory accredited by CNAS (China National Accreditation Service for Conformity Assessment), which can issue test reports covering filtration efficiency, dust holding capacity and resistance. These reports give you documented values to compare against your own acceptance criteria. Quality control follows IQC, IPQC and OQC across the production flow, so incoming carbon and resin, in-process moulding and finished sticks are each checked. The production base in Zhongshan, Guangdong, China, covers 50,000 m², including 6 clean workshops totalling 20,000 m². The company has held ISO 9001, ISO 14001 and ISO 45001 certifications, and in 2024 obtained IATF 16949 automotive quality management certification. Products comply with REACH and RoHS environmental regulations, and compliance documents can be provided. With more than 20 years of filtration R&D and manufacturing experience, Zanxis has developed over 1,000 filtration solutions and exports to Europe, the USA, Japan and South Korea. Multiple automated production lines support monthly output in the millions of pieces. OEM/ODM services cover dimensions, structure, filter media grade, end-cap material, logo and packaging.
To receive samples and the relevant test reports, please tell us your device or vehicle model (where applicable), the required size or a drawing, the airflow or water flow rate, operating conditions (pressure, temperature, water quality), and your estimated quantity. With these details Zanxis can confirm the closest standard size or propose a custom tooling route, and issue a spec sheet for your approval. Contact our team to start the sample verification process.
Yes. Zanxis operates a CNAS-accredited laboratory that can issue reports covering filtration efficiency, dust holding capacity and resistance. These reports are generated for the specific product and batch, so you can use them in your own validation file. Contact us with your required parameters to request the relevant report.
For standard Ф37.5×75 samples, stock is usually available and can be dispatched within a few working days. Custom sizes or formulations typically require 7–15 working days for sampling. The full validation depends on your own testing schedule; we recommend confirming the spec sheet before sampling to avoid repeated rounds.
The MOQ for standard Ф37.5×75 carbon sticks is typically 5,000–10,000 pieces, depending on packaging. Customised products are evaluated separately based on tooling and formulation. Standard batch lead time is 15–25 days; larger or custom orders are scheduled after sample approval.
General guidance for this product is every 3–6 months, depending on water quality and daily volume. Higher chlorine levels or higher usage will shorten service life. We recommend monitoring flow and taste, or following your appliance's replacement indicator, and confirming with your own water analysis.
Yes. Zanxis supports OEM/ODM customisation of length, diameter and inner/outer diameter ratios, as well as end-cap welding. The regular size is Ф37.5×75 mm, but other sizes in the table are for reference only; actual dimensions must match your drawing. Provide your housing drawing or sample for a precise match.
The carbon stick is designed for strong adsorption of residual chlorine, off-colours and odours, and the ion-exchange resin helps soften water and intercept heavy metals such as lead and mercury. Specific efficiency values are documented in the CNAS-accredited lab reports. Request the report for the exact figures you need to verify.
Yes, samples are available for evaluation. Standard sizes are usually free of charge, with the customer covering freight; custom samples may incur a tooling or sample fee. Please share your device model, required size, flow rate and operating conditions so we can prepare the right sample.
To quote accurately, we need your device or vehicle model, the required size or a drawing, the water flow rate, operating conditions (pressure, temperature, water quality) and estimated quantity. With these details we can confirm the standard size or propose a custom solution and send a formal quotation. <a href="/en/contact">Contact us</a> to proceed.