CR2 vs CR123A: Size, Voltage, and What Can Replace a CR2 Battery

A CR2 and a CR123A are both 3-volt lithium batteries, but they are different sizes and never replace each other. A CR123A is 34.5 mm long and 17.0 mm wide; a CR2 is 27.0 by 15.6 mm. That makes the CR123A about 7.5 mm (28%) longer and 1.4 mm wider, and it holds roughly 1.7 to 1.9 times the charge. The only batteries that replace a CR2 are other CR2s sold under different names, such as CR15H270, DLCR2 and EL1CR2.

CR2 vs CR123A at a glance

Is a CR2 the same as a CR123?

No. They share a chemistry and a 3-volt rating, which is why they get confused, but the size is different and size is what decides fit. A CR2 dropped into a CR123A compartment is 7.5 mm too short to reach both contacts. A CR123A will not go into a CR2 compartment at all. Do not shim a CR2 with foil or a spring: makers specify one cell type per device, and Leica’s rangefinder manual warns that “use of unapproved battery types may result in an explosion”.

“CR123” and “CR123A” are the same cell; Bushnell’s manuals write CR123, Energizer lists both names on one product.

What can replace a CR2 battery? CR2 equivalents

Any battery sold under one of these names is the same CR2 and fits the same compartment:

There is no other disposable battery that fits a CR2 slot. The 15266 and 15270 sizes you will see in listings are rechargeable cells, covered next. For which brand to pick, see the best CR2 battery for a rangefinder.

CR123A equivalents

The same applies the other way. CR123, CR123A, 123, CR17345, 5018LC, DL123A (Duracell), EL123 (Energizer) and K123LA all name the same 3-volt cell. The 16340 or RCR123A is the rechargeable lithium-ion version and runs at a higher voltage.

Rechargeable CR2 (RCR2) and RCR123A: the voltage problem

Rechargeable cells are sold in both sizes, as RCR2 or 15270 and as RCR123A or 16340. Most are lithium-ion, rated 3.6–3.7 V nominal and about 4.2 V straight off the charger. A disposable lithium manganese dioxide cell is 3.0 V nominal, with an IEC maximum open-circuit voltage of 3.7 V. So a freshly charged lithium-ion RCR2 runs above anything the device was designed around.

Some rechargeables are sold as 3.0 V, usually LiFePO4 chemistry. They avoid the over-voltage but hold less: one 400 mAh-rated 3.0 V CR2 delivered about half its rating in an independent test, against 800–930 mAh for a disposable CR2. If you want to stop buying batteries, a rangefinder with a built-in USB-C cell, such as the Blue Tees Series 3 Max+ or Captain, is the cleaner route.

Which golf rangefinders take a CR123A?

• Bushnell Pro X7 and Pro X7 Jolt. The English manual says “Insert a (CR123) 3-volt lithium battery”. The German section of the same PDF says CR-2, a translation error.
• Leupold RX-2800 TBR/W (hunting): “Battery: CR123”, more than 4,000 actuations.
• Bushnell Elite 1 Mile CONX (hunting): 3-volt lithium CR-123.
• Older Bushnell long-range lasers such as the Elite 1600 ARC and Pro 1M are listed against a CR123A by battery cross-references, but we could not confirm them in a Bushnell manual.

Every current Bushnell Tour and Pro golf laser, from the Tour V2 to the Tour V7 Shift and the Pro XE and Pro X3, takes a CR2: see Bushnell rangefinder battery by model. For every other brand, use the rangefinder battery finder.

Shelf life and cold weather

Both sizes keep for up to 10 years: Energizer says “up to 10 years in storage” for its CR2 and 123, Duracell guarantees 10 years, and Duracell’s datasheets give self-discharge under 1% after a year at 68 °F. In the cold, Energizer rates both sizes to −40 °F, Panasonic to −40 °F with a caveat below −4 °F, and Duracell and Varta to −4 °F. Leica’s advice for frosty rounds applies to any rangefinder: carry it close to your body and start with a fresh cell.

CR2 vs CR123A FAQ