Battery type 4LR44: Compatible cameras

The 4LR44 is a 6-volt alkaline battery consisting internally of four cylindrically stacked LR44 button cells (1.5 V each) in a common casing. Dimensions: 13 × 25.2 mm. From the late 1970s onward, it was used in numerous electronically controlled SLR cameras as a replacement for the previously common mercury-containing PX28. Manufacturers include Varta, Duracell, GP, and Energizer.

The 4LR44 is the standard power source for the entire Canon A series, including the Canon AE-1, AE-1 Program, A-1, AL-1, AT-1, AV-1, as well as the Canon New F-1 and F-1N. Other typical cameras include the Bronica medium-format series (ETR, ETR-S, ETR-Si, SQ, SQ-A, GS-1, EC-TL), the Hasselblad 2000 series (2000 FC / FCW), Contax RTS and RTS II, and various Fuji/Fujica AX and ST models. You can find the complete searchable compatibility list with 144 camera models above on this page.

The same cell is sold under many different names, depending on the manufacturer, market, and chemistry:

• 28A (ANSI/NEDA designation)
• PX28A, PX28AB: Alkaline
• A544 (Varta), V4034PX (Varta), V28PXL
• GP476A (GP), L1325 (Duracell)
• 4SR44 / S544: Silver oxide version, 6.2 V (slightly higher voltage)
• PX28 without a suffix. The historical mercury version (5.6 V, now banned throughout the EU)
• PX28L / 2CR1/3N: Lithium version (see next question)

Several cell chemistries can provide the same 6 V, each with its own strengths and weaknesses:

• 4LR44 / 28A (alkaline, 6.0 V): Standard, inexpensive and widely available. Voltage decreases continuously over the battery’s lifetime; this is not critical in cameras with a voltage regulator (Canon AE-1/A-1, see below), but in simpler circuits, the readings may drift toward the end of the battery’s life.
• 4SR44 / S544 (silver oxide, 6.2 V): Slightly higher voltage, but a very consistent discharge curve and longer runtime. More expensive than alkaline batteries, available from specialist photography stores.
• 2CR1/3N / PX28L (lithium, 6.0 V): Two 3 V lithium cells in one housing. The most consistent voltage throughout the entire discharge, resistant to cold, and with a long shelf life. Significantly more expensive.
• Adapter with 4 × LR44 individual cells: A sleeve adapter into which four separate LR44 button cells are stacked; the cheapest solution because LR44 cells are sold individually as standard button cells everywhere. Available from Ausgeknipst as a 4LR44 adapter.

As a general rule for analogue light meters without a voltage regulator: a higher-than-specified voltage makes the light meter assume there is more light → slight underexposure; a lower voltage conversely leads to overexposure. However, in the main cameras of this class—the Canon A-series (AE-1, AE-1 Program, A-1, AT-1, AV-1)—the electronics contain an internal voltage regulator that reduces the supply voltage from approximately 3.6 V to 7 V to a constant operating value. Within this range, alkaline (6.0 V), silver-oxide (6.2 V), and lithium (6.0 V) batteries produce practically identical readings. The voltage difference between the three chemistries is not critical here.

More important than the absolute value is the consistency of the voltage over the discharge curve: alkaline batteries gradually decline, while silver-oxide and lithium batteries maintain their voltage almost until the end. With modern Canon bodies, this is less important because of the regulator; with older or unregulated light meters, a lithium or silver-oxide cell is the technically cleaner choice.