Product Description
The DT4221 is a pocket-sized digital multimeter designed specifically for electrical work requiring optimal safety, with ±0.5% DC V accuracy and wide 40 Hz to 1 kHz AC V bandwidth.
- Achieving a high level of safety in a compact body and lightweight design
- Resistance and diode testing functions omitted by design in pursuit of added safety (DT4221)
- Voltage detection function (DT4221)
- Robust design capable of withstanding a drop from a height of 1 m
- ±0.5% DC V basic accuracy, wide 40 Hz to 1 kHz AC V frequency characteristics
- Low-pass filter cuts high harmonics (when measuring inverter fundamental waveforms)
- Broad -10°C to 50°C (14°F to 122°F) operating temperature range

Basic specifications
- DC Voltage range: 600.0 mV to 600.0 V, 4 ranges, Basic accuracy: ±0.5 % rdg. ±5 dgt.
- AC Voltage range: 6.000 V to 600.0 V, 3 ranges, Frequency characteristics: 40 Hz - 1 kHz
- Basic accuracy: 40 - 500 Hz : ±1.0 % rdg. ±3 dgt. (True RMS, crest factor 3)
- Resistance range: N/A
- Capacitance range: N/A
- Frequency range: AC V measurement: 99.99 Hz (5 Hz or more) to 9.999 kHz, 3 ranges / Basic accuracy: ±0.1 % rdg. ±2 dgt.
- Continuity check: Continuity threshold [ON]: 25 Ω or less (buzzer sound), [OFF]: 245 Ω or more Response time: 0.5 ms or more
- Diode test: N/A
- Voltage detection: 80 V to 600 V AC
- Other functions: Filter function, display value hold, relative value display, auto-power save
- Display: Main and Sub displays: 4-digits LCD, max. 6000 digits, bar graph
- Display refresh rates: 5 times/s (Capacitance measurement: 0.05 to 5 times/s, depending on measured value, Frequency: 1 to 2 time/s )
- Power supply: LR03 alkaline batteries ×1, Continuous use: 40 hours (backlight OFF)
- Dimensions and mass: 72 mm (2.83 in)W × 149 mm (5.87 in)H× 38 mm (1.50 in)D,190 g (6.7 oz) (including batteries and holster)
- Included accessories: Test lead DT4911 ×1, Holster ×1, Instruction manual ×1, LR03 alkaline battery ×1
Global Shipping
ROAExpo provides Global Shipping to over 130+ Countries worldwide.
All orders are shipped from our Central Logistics Hub, currently operated in South Korea, where ROAExpo directly performs free pre-shipment QQ Inspection (Quality & Quantity Inspection). Additional regional logistics hubs will be expanded globally in the future.
Available Shipping Methods
- Sea Parcel – Most economical option for heavy or bulk orders
- Air Parcel – Balanced option between cost and delivery speed
- EMS – International postal delivery service
- FedEx – Fast express courier service
- UPS – Premium international courier service
Shipping availability and transit time may vary depending on destination country and local regulations.
Shipping Cost Calculation
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Products from different brands or stores can be combined into one shipment when shipped from the same origin country.
You can combine products from multiple brands or stores in one cart to reach the USD $150 purchase threshold and receive shipping discounts, as long as the products are shipped from the same origin country.
The Final Shipping Cost Before Payment is clearly displayed at checkout. There are No Hidden Fees after payment confirmation.
Shipping Discount Benefits – Global Free Shipping (GFS)
- Orders over USD $150 with total shipping weight under 3kg may qualify for Free Shipping
- If total shipping weight exceeds 3kg, customers may receive up to USD $30 Shipping Discount
- The GFS Coupon (Code: ENJOYGFS-KOR) is automatically issued to eligible members and can be found in the member’s account after login. There is no limit on the number of uses.
- The GFS coupon may be combined with other promotions or coupons
- Eligibility may vary depending on product category, shipping method, and stock availability
Final discounted shipping cost is shown before payment confirmation.
Seasonal shipping promotions are announced on our homepage banners and member emails.
Order Processing & Tracking
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Once shipped, a Tracking Number will be provided to the customer.
Delivery time may vary due to customs clearance, local carrier operations, weather conditions, or public holidays.
Customs & Import Duties
Import duties, taxes, and customs fees may be charged by the destination country and are the responsibility of the customer unless otherwise stated.
Customer Support
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Returns Due to Defect or Shipping Error
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Returns for Change of Mind
Due to international shipping and customs regulations, returns for personal reasons may be restricted.
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Please contact Customer Support before initiating any return shipment.
Refund Processing
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Refund processing time may vary depending on payment method and financial institutions.
Non-Returnable Items
Certain products may not be eligible for return due to hygiene, safety, or manufacturer restrictions.
Customer Support
???? cs@roaexpo.com
☎️ +82-2-6951-0318 (Available Monday–Friday, 10:00–17:00 KST)