Amazon.com: Synergy Digital GPS Battery, Compatible with Trimble 92600 Survey GPS Battery Combo-Pack Includes: 3 x SDGPS-L1301 Batteries : Electronics
Item Location, the Interviewer–Respondent Interaction, and Responses to Battery Questions in Telephone Surveys - Kristen Olson, Jolene D. Smyth, Beth Cochran, 2018