Graco Pack ‘n Play Owner's Manual page 5

FOR SAFE BATTERY USE:
Keep the batteries out of children's reach.
Any battery may leak battery acid if mixed with a different battery type,
if inserted incorrectly (put in backwards) or if all batteries are not
replaced or recharged at the same time. Do not mix old and new
batteries. Do not mix alkaline, standard (carbon-zinc) or rechargeable
(nickel-metal hydride, nickel-cadmium) batteries.
Any battery may leak battery acid or explode if disposed of in fire or an
attempt is made to charge a battery not intended to be recharged.
Never recharge a cell of one type in a recharger made for a cell of
another type.
Discard leaky batteries immediately. Leaky batteries can cause skin
burns or other personal injury. When discarding batteries, be sure to
dispose of them in the proper manner, according to your state and
local regulations.
Remove batteries before storing product for a prolonged period of time.
Batteries left in the unit may leak and cause damage.
Recommended type batteries—alkaline disposables, 1-D (LR20-1.5V)
(not included). NEVER mix battery types. Change batteries when
product ceases to operate satisfactorily.
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