Renata Battery tester. No need to open the watch case. Tests 1.5v silver oxide and 3volt lithium coin batteries. Includes lithium battery for operation. Test watch on front of tester or test the battery individually on the side of the tester. Great visual tester to use in front of customers to indicate if the battery is low or that the watch itself has other mechanical issues, and needs further investigation.
BWT94 comes in original box, fully packaged, unopened and with instruction booklet.