The iPhone 7 and 7 Plus will be difficult to find in stores on Friday

Voracious demand is to blame. In a break from long-standing tradition, Apple declined to announce first-weekend sales figures for the iPhone 7, but major carriers in the United States have reported record-breaking pre-orders ahead of the iPhone 7’s launch on September 16. On Tuesday, T-Mobile executive John Legere revealed via Twitter that the iPhone 7 broke the carrier’s all-time single day sales record — its “biggest launch ever.” Sprint chief Marcelo Claure, meanwhile, said that iPhone pre-orders were up more than 375 percent in the first three days of availability. And on Wednesday, AT&T financial chief John Stevens said during a CNBC webcast that iPhone sales were “exceeding … expectations.”

Unsurprisingly, that appetite has led to supply constraints across Apple’s sales channels — including its own brick-and-mortar stores. Apple spokesperson Trudy Miller said that “all finishes” of iPhone 7 Plus “[would] not be available for walk-in customers,” and that the iPhone 7 would only be available only “limited” quantities on launch day. “We sincerely appreciate our customers’ patience as we work hard to get the new iPhone into the hands of everyone who wants one as quickly as possible,” she said. “We couldn’t be happier with the initial response to iPhone 7 and iPhone 7 Plus, and we are looking forward to beginning sales through our retail stores and partners around the world.”

One particular model of iPhone is proving especially elusive: jet black. Miller said that iPhone 7 models in jet black would only be available for purchase online, via Apple.com, and TechCrunch corroborated that scarcity on Thursday. “Jet black iPhone 7s are incredibly hard to come by — even for employees and executives inside Apple,” reporter Matthew Panzarino wrote, citing unnamed sources. “Most reviewers and other early birds got matte black iPhone 7 Pluses to test.”

Those who do brave the crowds at their local Apple store will have to exercise patience. Apple said that, as in years past, iPhone 7 models will be sold on a first come, first served basis.

The familiar fervor around iPhone launches likely isn’t the only factor in this year’s models’ meteoric success. Another contributor’s likely the controversy around Samsung’s newest flagship, the Galaxy Note 7 — defective batteries have caused a number of Note 7 handsets — as many as 90 in the past month, according to a new report — to catch fire while charging. That’s prompted high-profile parties from the U.S. Federal Aviation Administration, Australian airline operators Qantas, Jetstar, and Virgin Australia, and India’s Directorate General of Civil Aviation (DGCA) to New Jersey’s Stockton University curtail the smartphone’s operation.

Samsung’s initiated a global recall of all 2.5 million units sold so far and begun issuing exchanges and refunds to eligible customers, but the electronics behemoth continues to be dogged by dramatic new developments: on Thursday, the Wall Street Journal reported that Samsung was late in coordinating with the Consumer Product Safety Commission, the federal agency tasked with overseeing product recalls.

Wall Street is pleased with the iPhone 7’s performance so far, unsurprisingly. As of publication time, Apple’s shares were trending upward at $115.08 — up 3.31 percent since the chime of Thursday’s starting bell.

The company, for its part, hopes to ship as many as 100 million iPhones this year, and is reportedly its manufacturing partners to help it reach that goal. It would be a new record for the company.