Published 12/03, Copyright 2003,

The K-4 Factor
A WheelchairJunkie's Guide to Lightweight Manual Wheelchairs

By Mark E. Smith

So, you're a full-time powerchair user, and the only time you use a manual wheelchair is when your powerchair is in for service, or when you're traveling out of necessity in someone else's car, stowing your folded manual in the trunk.  Maybe you use a manual, say, ten or twelve times per year.  Nevertheless, when you do use your manual, it's like pushing a log - a steel-framed, vinyl-upholstered, brakes-slipping chair that's no better than those rolling around the community hospital.  An ultralight manual chair would be great, but ranging in price from $1,800 to $3,000, your insurance won't fund it as secondary mobility, and that's too much to pay out-of-pocket.  Maybe that granny-type chrome goliath manual chair in the closet isn't so bad after all?

Well, fortunately, with a little product knowledge and an eye toward the right components, there's a genre of manual chairs that offers improved performance, without breaking the budget or tempting insurer rejection - the K-4 factor, that is.

The label K0004 is a Medicare/Medicaid reimbursement code for a manual wheelchair weighing 34lbs. or less (typically, K-4s range from 29lbs to 33lbs.).  Now, if you're using private insurance or paying out-of-pocket, the literal K0004 code doesn't apply; however, much like the term SUV applies to a class of vehicles in the automobile industry, K-4 is the term used for the product genre of a lightweight folding manual chair somewhere between an everyday ultralight and a hospital-type chair - and one that's readily fundable by many insurers as a secondary chair.

Pricing on K-4s is typically half that of an ultralightweight, putting retails around $950.  The reason why K-4s cost so much less than their 5lb.-lighter counterparts is because K-4s are somewhat limited in their componentry.  For example, whereas an ultralight may have an angle-adjustable backrest and 24-position rear axle as standard, a K-4 may have a fixed back angle and 4-position rear axle mount.  And, again, for many users of manual chairs as back-up mobility, these limited features may be the most practical - after all, why pay extra for complex features you may not need?

But, this isn't to say that K-4s lack meaningful features.  Industry standards on K-4s include adjustable back heights, adjustable seat-to-floor heights, and flip-back armrests.  On some models, angle-adjustable caster barrels, quick-release rear wheels, and adjustable-tension seat upholstery are also standard.  The key, then, is to know what to look for in a K-4, getting the most out of this affordable genre.

Among the biggest misconceptions regarding K-4s is that they're all the same.  It is true that there is less variation in frame styles than with higher-end chairs - as K-4s are traditional box-frame folders - but features can vary greatly from model to model.  If you wish drop-in legrests, the Breezy 510 by Sunrise Medical has them.  If you wish quick-release axles as standard, the Stylus by Pride Mobility has them.  And, if you wish optional frame colors, the 9000XT by Invacare has them.  As a consumer, it's important to study the order forms, from wheels to upholstery, and determine which model offers the features you need, in the most affordable package (again, if a feature like angle-adjustable caster barrels is important because you need seat angle for positioning, the cost can vary from included as standard on one model to $125 extra on another model).

Hints for Selecting and Configuring a K-4

-Study carefully the standard rear wheels and tires.  Many K-4s come with a 24"x1" molded "economy" mag assembly in which the tires aren't replaceable (when the tires wear, you have to replace the whole wheel).  If you're using the chair outdoors at all, look for a 24"x1-3/8 wheel assembly, where the tires are replaceable and interchangeable with pneumatics.

-If self-propulsion is important, look for an axle-mount that allows the rear axles to be repositioned slightly forward of the backrest.

-If the chair will be mostly propelled by an attendant, 22" rear wheels will make the chair more compact, and reduce wheel interference during transfers.

-For enhanced indoor maneuverability, consider selecting 6" casters, which are often a no-charge option.

-The standard flip-back arms on K-4s completely clear the sides of the chair, making an upcharge for a secondary complete removable option unnecessary for most users (if attendant transfers are used, removable arms may be helpful, as flip-back arms can interfere with lifting positions from behind the chair).

-Select an appropriate seat-to-floor height (standard is usually 17.5" to 19.5", with 15.5" and 16.5" as upcharge options).

-Don't overlook the use of a seat cushion, making sure the chair's seat dimensions and seat-to-floor height are appropriate for the intended cushion.

-The most telling signs of assessing K-4 quality is seen through the durability of the legrests, effectiveness of the brakes, and alignment of the flip-back arms - look for these check points.

Image of breezy510.jpg
Breezy 510 by Sunrise Medical

Image of pridestylus.jpg
Stylus by Pride Mobility

Image of 9000xt.jpg
9000XT by Invacare

Indeed, K-4s aren't the sexiest products on the market.  However, with an eye on features and configuration, you can leverage the K-4 factor, ending up with meaningful and somewhat stylized mobility, at a fundable price.

Image of menubarpage.jpg