What it means
The model splits a customer relationship into two prices: a low, visible entry price that removes the barrier to buying, and a higher, recurring price on something the customer will keep needing. Because the second purchase is only attractive to someone who already owns the device, the installed base becomes the real asset.
It matters because it changes what a finance team should measure. Unit profitability on the device is deliberately thin or negative, so judging the business on that number alone will always look alarming, and the meaningful figures are attach rate, refill frequency and lifetime value per installed device.
Making the model work requires some form of lock-in, whether that is a patented cartridge shape, a chip that authenticates the refill, a warranty condition or simply a strong habit. Without it, a third party will copy the consumable at half the price and the economics collapse, which is why compatibility disputes and litigation are common in these markets.
The approach is not limited to hardware. Software companies price a low entry tier and charge for extra seats or usage, medical device firms place instruments cheaply and profit on the reagents, and equipment makers supply a machine on the condition that all service parts come from them.
The main risks are the payback period and the customer mix. Cash goes out on subsidised devices before it comes back on refills, so a fast-growing business can be profitable on paper yet short of cash, and light users may never buy enough consumables to repay the subsidy they received.
In practice
Real-world examples.
Example
A coffee machine brand sells its entry model at $79 when it costs $96 to build, a subsidy of $17. Each pack of pods sells for $9 with a margin of $5, and the average household buys about 30 packs a year. The subsidy is recovered after 3.4 packs, or roughly six weeks of normal use.
Example
A laboratory equipment supplier places analysers in hospitals at no upfront charge and signs a five-year contract for the test kits they consume. The hospital avoids a capital request it would struggle to get approved, and the supplier earns a predictable margin on every test run.
Example
A console maker sells hardware at a loss for the first two years of a generation and earns a royalty on every game sold. When a rival platform attracts more exclusive titles, the hardware loss stops being recoverable and the company is forced to raise the console price mid-cycle.
Formula
Calculation
Lifetime value per customer = Margin on the device + (Margin per consumable x Consumables per year x Expected years)
A home printer sells for $60 and costs $90 to make and ship, giving a margin of -$30. Each cartridge sells for $35 and costs $12, a margin of $23. A typical household buys four cartridges a year and keeps the printer for three years, so it buys 4 x 3 = 12 cartridges, generating 12 x $23 = $276 of consumable margin. Lifetime value is -$30 + $276 = $246 per printer. The subsidy is repaid once the customer has bought $30 / $23 = 1.3 cartridges, which is roughly four months into ownership, and everything after that is profit.Case study
Seen in the real world.
Vellum Filtration is a fictional maker of water filter jugs, used here as an illustrative example. It sold the jug for $22 against a build cost of $31, accepting a $9 subsidy per household, and made its money on replacement filters priced at $8 with a margin of $5.20. At the expected six filters a year, the first-year margin per household was -$9 + (6 x $5.20) = $22.20.
Two years in, generic filters appeared online at $4. Vellum's attach rate fell from six filters a year to about 3.5, cutting the first-year margin to -$9 + (3.5 x $5.20) = $9.20 and leaving the business barely covering its subsidy. Management responded with a subscription: eight filters a year delivered automatically at $6.50 each, a margin of $3.70 per filter. The lower price per filter was offset by the higher volume and near-total retention, producing -$9 + (8 x $3.70) = $20.60 in the first year, and a far more predictable second year.
Watch out
Common mistakes.
- Judging the model on the margin of the first sale. The device is deliberately priced to lose or barely break even, and a manager who cuts the subsidy to protect that margin usually shrinks the installed base and the profit with it.
- Assuming lock-in lasts forever. Patents expire, chips get reverse-engineered and regulators sometimes intervene, so the consumable margin should be treated as something that erodes rather than something guaranteed.
- Ignoring the cash gap. Every new customer consumes cash before repaying it, which means rapid growth can starve the business even when the lifetime economics are excellent.
Questions
People also ask.
Is this the same as a loss leader?
Not quite. A loss leader is priced low to bring people into a shop where they may buy anything, whereas the razor-razorblade model ties the cheap item to one specific consumable that only that item can use.
How do you know if the model is working?
Track the attach rate, meaning consumables sold per installed device per year, and the payback period on the subsidy, because both will move long before the reported profit does.
Does it work for services?
Yes, in the form of low-priced onboarding or a discounted first year followed by full-price renewals, though the lock-in there comes from switching cost and data rather than physical compatibility.
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