What are the speed grades for different capacities?

32GB is U1, 64GB/128GB/256GB/512GB is U3. 32GB-Class 10, UHS-I (U1), 633x (Max up to 95MB/s read, 20MB/s write). 64GB/128GB/256GB Class 10, UHS-I (U3), 633x (Max up to 95MB/s read, 45MB/s write). 512GB Class 10, UHS-I (U3), 633x (Max up to 100MB/s read, 70MB/s write).

High-Speed U3 Mini Memory SD Card Plastic TF Card in Sizes 256GB Compatible with DVR

Name: High-Speed U3 Mini Memory SD Card Plastic TF Card in Sizes 256GB Compatible with DVR
Brand: Shenzhen Xingshidi Technology Co., Ltd.
SKU: 2271072905

Guangdong, ChinaShenzhen Xingshidi Technology Co., Ltd.

US$25.00

50-499 Pieces

US$20.70

500+ Pieces

Sample price:US$30.00/piece.Request sample

Product profile

Customization

Available

Capacity

32GB

Type

TF Card

Model NO.

256GB

Memory Card Application

Cell Phone

Interface

ExpressCard Slot

Card Slots

Single

Installation

Internal

Speed Grade

Class 10

Transport Package

Blister

Specification

Wafer

Trademark

DATA

Origin

China

HS Code

8523511000

Production Capacity

50000/Day

Key features

Wide Capacity Options: Available in 128MB to 512GB sizes including 32GB, 64GB, 128GB, 256GB, and 512GB.

High Speed Performance: Class 10, UHS-I U3 speeds up to 100MB/s read and 70MB/s write on 512GB model.

Broad Device Compatibility: Works with desktops, laptops, cameras, drones, tablets, and vehicle recorders.

Durable Material: Constructed with epoxy resin for reliable data storage in various environments.

Certified Quality: Products hold CE, FCC, and ROHS certificates; factory has SGS, TUV, BV certification.

Customization Service: Factory supports product customization according to customer design requirements.

Strict Quality Control: Includes pre-production samples, 100% final inspection, and H2/H5 testing.

Company profile

Fast Delivery

Shenzhen Xingshidi Technology Co., Ltd.

Guangdong, China

Business Type: Manufacturer/Factory, Trading Company CertifiedExport Year: 1 Month CertifiedNearest Port: Shenzhen PortAverage Response Time: ≤5.31h CertifiedTerms of Payment: LC, T/T, PayPal, etc. CertifiedInternational Commercial Terms(Incoterms): FOB, CIF, CFR, EXW

AI-Powered supplier vetting

SummaryShenzhen Topfine Technology Co., Limited is a China-based limited company described across the records as both a trading company and manufacturer/factory, supplying flash drives and related storage products. It reports broad customization and ODM capabilities, new products within the past year, extensive export coverage, and an off-peak lead time within 15 working days. However, the available quality and service-control evidence is weak: no written corrective-action or complaint-handling procedures are reported, quality assurance and traceability statuses are unknown, and quality-control test equipment is recorded as zero. A TUV Rheinland audit record is present, but its evaluation result is recorded as 0 and the report validity ended in 2025. Financial information is represented only by years, without substantive financial performance evidence. No customer cases or named-brand OEM references are provided.

Supplier typeThe supplier is identified as Shenzhen Topfine Technology Co., Limited, a China-based limited company. Its records classify it as both a trading company and manufacturer/factory, while its stated business scope includes electronic products, computer peripherals, U disks, and import/export activities; another record lists medical-device-related licensed projects, creating some scope inconsistency.

After-Sales capabilityThe supplier reports no written procedures or records for corrective and preventive actions or effective customer-complaint handling. This is explicit evidence of a documented service-process deficiency.

R&D capabilityThe supplier states that it had new products during the past year and provides ODM services, indicating some product-development capability. It also reports no available SDK, but the absence of an SDK is not by itself evidence that its general innovation capability fails the field.

Production capacityThe supplier is described as a manufacturer/factory and reports production of storage-related products including HDDs, SSDs, micro SD cards, USB flash drives, and memory cards, with stated output of 5,000,000 pieces. However, its quality-control test-equipment quantity is recorded as zero, while quality assurance and traceability statuses are unknown, weakening confidence in production-control maturity.

Customization capabilityThe supplier explicitly offers customization from samples, designs, full customization, minor customization, and flexible customization, and also states that it provides ODM services. These records directly support broad customization capability.

Product Q&A

Q:Who are we?

We are topfine in Guangdong, China and started in 2012, selling to North America (40.00%), Eastern Europe (8.00%), Western Europe (10%), Domestic Market (2.00%), Africa (3.00%), Oceania (1.00%), East Asia (30.00%), Central America (5%). In total, there are about 80 people in our office.

Q:How do we ensure quality?

Always pre-production samples before batch production; Always final 100% inspection and Pass H2 and H5 test before shipment;

Q:What can you buy from us?

USB flash drive, USB chipset, UDP chipset, TF card, SD Card, SSD, RAM, SSD, Hard disk

Q:Why should you buy from us instead of other suppliers?

Our factory has more than 15 years' experience to produce usb drive. We can customize the product according your design, we have own development to develop new products every year, we service many famous big company and OEM for famous brands, quality is our first, fast lead time and best after service All our products have CE, FCC and ROHS certificates. SGS, TUV, BV certification for our factory

Q:What is the capacity difference between manufacturer and PC?

32GB = approximately 28GB-30GB, 64GB = approximately 58GB-60GB, 128GB = approximately 115GB-120GB, 256GB = approximately 230GB-238GB, 512GB = approximately 460GB-476GB. This is calculation difference between manufacturer and your PC, please Google 'Memory card capacity' to get more information. Your PC says 1GB = 1.073741824 Billion bytes where Market Defines 1GB = 1.00 Billion bytes.