Nielsen-Kellerman Company designs, manufactures and distributes rugged, waterproof environmental and sports performance instruments for active lifestyles and technical applications, including Kestrel Weather & Environmental Meters, NK Electronics for Rowing and Paddling, and Blue Ocean Rugged Megaphones & PA Systems. Nielsen-Kellerman has been in business for more than 30 years, and has focused relentlessly on meeting the specialized measurement needs of demanding outdoor customers. Olympic athletes, firefighters, and military professionals are just some of the NK customers who rely on our products for accuracy and durability. Delivering anything less than the highest level of quality is not an option.

Company details

21 Creek Circle , Boothwyn , PA 19061 USA


View in map

Find locations served, office locations, manufacturers and our distributors.

Business Type:
Industry Type:
Meteorological Monitoring
Market Focus:
Globally (various continents)

Whatever the niche, we know our customers won't forgive us for letting them down, and will tell their friends what they think of us, good or bad. From order entry to customer support for the life of our products (and beyond), when our customers call, email, tweet (@KestrelWeather or @NK_Performance) or Facebook us, we bend over backwards to keep them happy.

Every NK product undergoes rigorous functional and sealing testing and, where applicable, calibration against NIST-traceable standards, before it leaves the plant. Every product is also covered by a full warranty against defect or failure to perform (two to five years depending on product). Beyond the warranty period, we do all we can to keep our customers in the NK family with our Customer Warranty Program that provides a generous trade-in allowance towards a replacement NK product, no matter the age or condition of the product being replaced. We know that convincing customers to purchase a product is just the first step -- once you're an NK customer, we want you to stay one for life! We're proud of our tremendous repeat and referred customers and virtually non-existent return rate.

Innovative US Manufacturer

NK began business in an upstate New York basement, and we remain committed to US manufacturing to this day. Now located in Boothwyn, PA, we design here in the US, we source all the parts we can in the US, and we build here in the US. We continuously improve our product, processes, flow, inventory management and people to stay cost-competitive and ensure we can deliver what our customers need when they need it.


We strive to conduct our business in a sustainable manner and minimize harm to the environment by actively implementing company-wide plans to conserve energy, reduce waste, and recycle. We conduct life-cycle analysis of shipping impact to determine the most effective packaging for each product and minimize 'shipping air.' We use recycled products in packaging where the benefits are clear.

Giving Back to the Community

After 30 years, we've got a lot of friends in some close-knit communities. We appreciate our customers and friends, and focus our charitable activities on giving back to the communities that support us and our employees. We donate over 2% of our pretax profits to charitable organizations that we believe are helping make the world a better place in ways relevant to our customers.

In rowing, NK has partnered with USRowing to ensure that the National Team coaches, boats and athletes are outfitted with the latest NK electronics. NK also supports the rowing community at all levels by awarding annual development grants to both rowing programs and individual athletes who are striving towards a goal.

Richard Kellerman and Paul Nielsen established NK in 1978. Richard was working as a Physical Chemist at Xerox Inc., when Coach Ted Nash recruited him to devise a product that would simplify the coxswain's many jobs on the river.  With the collaboration of Paul Nielsen, an associate from Xerox Inc., Richard Kellerman was convinced that he could create one unit to combine the tasks of an amplifier, stroke meter and timer to simplify the coxswain's job. The idea to create a CoxBox amplifier came to Richard after watching a coxswain run his crew into a bridge during a regatta.

In 1984, NK expanded their product line to include the original StrokeCoach stroke meter, designed for scullers and straight boats so that they, too, could know their stroke rate and time. Following the success of the StrokeCoach, NK designed the Chronostroke rate and stopwatch for rowing coaches, and developed and manufactured the original monitor for the Concept II rowing machine. With the development of these four products, NK had grown too large for the basement of Richard's house. In 1985, NK took up residence in an old rayon-making factory in Marcus Hook, PA, developing the Pace Coach and the SpeedCoach over the next 10 years. During this time, NK also redesigned the CoxBox, CoxVox and StrokeCoach to be smaller, lighter and easier to use.

In 1996, NK expanded into a completely new product line by launching a line of wind and weather instruments, called Kestrel® Weather & Environmental Meters. The company was growing rapidly, so once again it was time to move to a larger facility located in Chester, PA. During the tenure at the Chester facility (1996-2004), NK released a total of 4 models of Kestrel Weather & Environmental Meters, as well as added another product to the rowing line, the SpeedCoach Gold, and introduced the Interval 2000 Rate Watch® for the swimming and track and field markets.

In 2009, NK expanded its business and facilities to a brand new manufacturing location in Boothwyn, PA. Along with NK's ever growing staff, the rowing product line has grown to include the easy-to-use SpeedCoach XL. The CoxBox got another facelift making it more appealing and user-friendly. The Kestrel Weather & Environmental Meters family diversified in order to meet the needs of various industry professionals by launching five new Specialty Kestrel Meters.

Looking toward the future, NK is never one to rest on its success. There are many new products currently under development and testing that will become available in the near future. Be sure to keep an eye on this website for the very latest from Nielsen-Kellerman.