Dual Frequency Key Fob

Dual Frequency Key Fob

Built-in Chips

Two completely independent chips:

• HF chip: Genuine NXP NTAG213, 144 bytes user-writable memory
• LF chip: EM4100 / TK4100 compatible, read-only, card number fixed at factory (can't be changed later)

HF works at 13.56 MHz, LF at 125 kHz. Both chips work totally separately, zero interference.

Why Choose Dual-Frequency?

A lot of customers run into this exact problem: the company just upgraded to IC card access control, but the staff dorms are still on the old ID system. The two don't talk to each other. One of our dual-frequency fobs solves both doors with a single tag - no need to carry two cards. Property-management system integrators buy them in bulk too because buildings often have readers installed years apart that aren't compatible.

Material & Build Quality

• Shell: Brand-new ABS (not recycled material), tough and flexible, won't crack in cold weather
• Encapsulation: Coils placed → filled with epoxy resin → cured → ultrasonic welded shut. Extremely solid.

Colors

Black always in stock (by far the most popular). Blue, red, green, yellow also ready to ship. Any other color: MOQ 500 pcs.

Printing Options

• Silk-screen (cheap, perfect for simple logos/text)
• Laser etching (super sharp even on small text, never wears off)
• UV full-color printing (photos, gradients, etc. - higher price)

Size & Specs

37 mm × 31 mm × 5.5 mm

Hole diameter ≈ 4 mm - fits any standard lanyard or keyring

Weight ≈ 5 g each, very light

Performance

• Read/write cycles: HF > 100,000 times. LF read-only = no wear
• Read range: Tested with ACR122U (HF): rock-solid when touching, still works 3-4 cm most of the time. LF with normal ID readers similar distance
• Temperature: -25 °C freezer 4 hours & 70 °C oven 2 hours - both passed
• Water resistance: Soaked in tap water 24 hours, wiped dry, works perfectly. Don't swim or hot-spring with it.
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Packing

• Loose: 100 pcs per zip-lock bag
• Full carton: 2,000 pcs (20 bags), five-layer corrugated box ≈ 38 × 20 × 28 cm, gross weight ~12 kg
• Custom color box / individual packaging available (extra cost)

Lead Time

• Stock colors/no logo: Ship within 3 days after payment
• Silk-screen logo: 7-10 days after payment
• Custom color or custom shape (new mold): 25-30 days + mold fee

Payment

• Small orders: PayPal (you cover the fee)
• Big orders: T/T, 30 % deposit, balance before shipment
• Alibaba Trade Assurance welcome - full buyer protection

Shipping

Default international express (DHL/FedEx/UPS - we choose the cheapest to your door). Freight collect or prepaid, just tell us.

Large volumes can go by sea - we provide all customs documents.

Quality Control

100 % tested for frequency and read/write before shipping. Defective ones are removed. We've been doing this 15+ years - we don't mess around with quality. Any issue on arrival → send a quick video → we replace or refund immediately.

Samples

Free samples anytime. You only pay shipping (collect or transfer the fee). Highly recommend testing on your own equipment first to avoid headaches later.

Certificates

CE and ISO9001 available - scans sent after order confirmation.

Questions? Just ask - we reply fast and keep things simple!

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