Individual solar cells are somewhat difficult to solder to. Self-adhesive metal stained-glass tape makes for the easiest soldering job--the tape holds itself in place while you solder. Use electronics solder that contains 2% silver. One side of the cell is (+), the other (-).
rain check (plural rain checks) (idiomatic) Any voucher or note from a merchant to a customer to provide an item the merchant has run out of at a later date for the item's current price, or (in a more literal sense) to provide a service at a later date.
Check. A written order instructing a bank to pay upon its presentation to the person designated in it, or to the person possessing it, a certain sum of money from the account of the person who draws it. A check must contain the phrase pay to the order of..A check differs from a draft in that a check is always drawn on a bank, while a draft is an order for payment drawn on anyone, including a bank, a person, or a trading account with a company. cashier's check is one that the bank draws on itself and is signed by an authorized bank official. The bank lends its credit to the purchaser of the check in order to facilitate its immediate use in commercial transactions.