ProTek R/C 4S Li-Poly 20C Battery Pack (14.8V/2100mAh) (Starter Box)

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This is the ProTek R/C 4S 2100mAh, 20C Lithium Polymer battery pack. This pack has T-Style Ultra connectors pre-installed, and comes with a 5-pin Align/E-Flite style balance connector.

This battery will also make an excellent starter box battery for R/C Cars! You can significantly reduce the weight of your starter box, as one of these batteries will weigh less than one third of two 3600mAH NiMH packs (221g vs 802g). This will make your starter box almost 1.3 pounds lighter! Not to mention they will have increased voltage and punch, making it easier to start a tight engine.

Unlike most other Lithium Polymer batteries, these batteries can be charged at up to 2 times the rated current, or 2C! If your charger is capable, you can charge these batteries at 4.2A!



  • Type: Lithium Polymer
  • Capacity: 2100 mAh
  • Voltage: 14.8V nominal
  • Connector Type: T-Style Ultra (14 GA Wire)
  • Balancer Type: Align/E-Flite compatible (XH)
  • Number of Cells: 4
  • Weight: 221g
  • Configuration: 4S1P
  • Dimensions (WxLxH): 37 x 105 x 29mm
  • Maximum Charge Rate: 2C (4.2A)!
  • Maximum Continuous Discharge: 20C (42A)
  • Maximum Burst Discharge: 40C (84A) for 3 seconds

1) DO NOT leave the battery in your model when charging
2) DO NOT leave unattended when charging
3) ALWAYS balance charge the battery
4) ALWAYS use a LiPo charging bag
5) YOU MUST use a Li-Poly specific charger to charge the pack (NiMH or NiCD only chargers WILL NOT WORK!)
6) YOU MUST not over discharge the Li-Poly battery pack
7) READ & UNDERSTAND the instructions carefully before operating this battery

NOTE: When using high energy Li-Polymer Batteries, please do not over-discharge or over-charge batteries as this will result in over heated batteries. Discharging capacity can't exceed 80% of the max capacity of the pack after full charging to ensure a good cycle performance. It is recommended to fully charge a brand new battery before using and only discharge the battery 50% for first 5 cycles. Always monitor race time and/or set a low voltage warning on ESC (End voltage cannot be lower than 3.2v per cell) Do not use the battery that has too low a voltage.

Do not expose batteries to sunshine or store/charge batteries at the temperature above 35C or in a closed car. The high temperature environment could cause damage to the pack or make it burst. If the battery becomes hot while fast charging, high current discharging or racing, do not charge the battery until it has cooled completely. Wait about 20 mins, then inspect prior to recharging.

ProTek R/C is an brand.

This product was added to our catalog on May 5, 2010.

Marcus Izzo
I have been using this in my Ofna truggy starter box for a year now and has been flawless, A+ lipo!
Brian Rock
Verified Owner
Lightweight pack and it balances out well every charge. Good for a full day at the track!
chad bradley
Verified Owner
Last a long time and has plenty of power in my Ofna Truggy Start starter box
Kah Chik Yong
Verified Owner
Perfect battery for my mugen starter box. Works awesome 6 months in. Worth the money.
Skye Baker
Verified Owner
This battery is perfect. I was a little hesitant at first because of the small size. I was going to be using this to break in a new Orion engine which are known to be pretty tight, and was worried about running out of juice. Happy to say it passed with flying colors and then some! I have never even came close to running this thing down, even after a full day of starting issues and multiple uses. The small size of the battery combined with the ultra light low profile Hudy Star Box, makes for one of, if not the lightest setups out there!
Derrick Poe
Verified Owner
Great Lipo. Money well spent. Powers Truggy box easily. Protek=GOOD!!!!
Lamar Martin
Verified Owner
I purchased this battery at the beginning of the 2013 on road racing season at Blue Diamond Park. This battery provides an enormous amount of power throughout two day race events plus another one day event the next week without requiring an additional charge. This single battery has dramatically reduced the weight of my starter box making trip to pit lane easier! All-in-All this is a GREAT battery even though it is $13 more than its bargain basement cousin!! I recommend this battery highly!!
Curtis Door
Verified Owner
By far the best starter box battery I've used. It has plenty of power to start new engines and will last a few races on one charge. I'm still using the one I got two years ago without a problem!

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