• WeinCell Replacement Battery MRB400 Thumbnail
  • WeinCell Replacement Battery MRB400 Thumbnail
  • WeinCell Replacement Battery MRB400 Thumbnail
  • WeinCell Replacement Battery MRB400
  • WeinCell Replacement Battery MRB400
  • WeinCell Replacement Battery MRB400

WeinCell Replacement Battery MRB400

$9.99

  • Compatible with any Pentax camera specifying RM400R or V400PX mercury cells.
  • Voltage output more stable than alkaline replacements.
  • No camera adjustment needed.
  • Environmentally safe.

Long Live Analog!

WeinCells are the only mercury-free, exact-voltage replacements for discontinued 1.35 volt mercury photo batteries. The zinc/air composition of the WeinCell delivers the same precise voltage discharge curve with steady, constant output identical to that of the banned mercury oxide batteries (alkaline replacements are generally 1.5 volts, with an unstable output curve; this can result in exposure errors of up to 2 stops).

These environmentally friendly batteries are compatible with any camera or meter specifying the listed mercury battery. Voltage output is more stable than alkaline replacements. No camera/meter adjustment or adapter required.

Compatible With

Pentax ​Spotmatic camera

​Pentax Spotmatic II camera

​Pentax Spotmatic IIA camera

​Pentax SP500 camera

​Pentax SP1000 camera

Technical Specs

  • Voltage:1.35
  • Fuel Cell:Zinc-Air
  • Width:1.2 cm
  • Length:1.2 cm
  • Height:4 mm
  Mercury Battery Alkaline Battery WeinCell Battery
Environmentally Safe Yes Yes
Stable Power Yes Yes
Allowed in USA Yes Yes
Made for Cameras Yes
Made for Meters Yes
Long-lasting Yes Yes
No Adjustment Needed Yes Yes
Non-toxic Yes Yes

Supporting Research

See All Articles

Customer Reviews/Anecdotes

Submit Your Review

Restoring my faith and the possibility that someone still cares about their work.

Imagine my surprise when my new l50MM arrived in the mall yesterday... free of charge. Why was I surprised? Because I've just spent the last few weeks being disappointed time and again by my cable company, phone company, auto mechanic and all the other people and organizations who are happy to take my money,... read more >

Imagine my surprise when my new l50MM arrived in the mall yesterday... free of charge. Why was I surprised? Because I've just spent the last few weeks being disappointed time and again by my cable company, phone company, auto mechanic and all the other people and organizations who are happy to take my money, but rarely provide the goods or services they've promised.
Clearly, Wein belongs In a category by itself.

Not only are your products excellent, but apparently you're also willing to stand behind them and make sure they deliver what was promised. I thank you for restoring my faith and the possibility that someone still cares about their work.

Happy Holidays!  < read less

— Kevin M.

What a great company!

I cant help but spread the word about how great of a company this is and how much your products help me.

I cant help but spread the word about how great of a company this is and how much your products help me.  < read less

— Louis D.

You Might Also Like

WeinCell Replacement Battery MRB675

WeinCell Photo Battery MRB675

$9.99

Replacement battery for cameras and exposure meters. The perfect replacement for PX675 mercury batteries 1.35 V. Manufactured in strict accordance with international specifications for 'green' cells and contain no mercury.

WeinCell Replacement Battery MRB625

WeinCell Photo Battery MRB625

$9.99

Replacement battery for cameras and exposure meters. The perfect replacement for PX625 and PX13 mercury batteries 1.35 V. Manufactured in strict accordance with international specifications for 'green' cells and contain no mercury.

*Does not remove 100% of listed particle from air.