Like TG said directly behind can be a little dangerous clamping and its probably not necessary.
If you measure girth from head backward you’ll find that if you’ve been clamping near the base your girth is maxed out usually right around the mid-shaft & where your circumcision scar would be if your circumcised. Clamp squeeze or jelq from there and the part directly in front of it will start to grow.
IF you decide to clamp just the head be careful, pay attention, and if you feel any pain, tingling, or numbness stop immediately.
September 1, 2016 - BPEL: 6.675in MSEG 4.75in EL: 5.5in FG 3.75in FL 3.5in
November 28, 2023 - BPEL: 8.5in MSEG 5.75 EL: 8.5in FG 5.0in FL 5.25in
PE Goal - (set 9-1-2016) BPEL: 8.5in MSEG 6.5in EL: 8.0in FG 5.5in FL 6in | NEW PE Goal - (set 11-28-23) BPEL 9.25in MSEG 6.5in EL 9.0in FG 5.5in FL 6in