To meet the comfort requirements of contemporary acupuncture clinical practice

this study customized 8 specifications of fine elongated-needles

i.e. 0.16 mm×100 mm

0.18 mm×100 mm

0.20 mm×100 mm

0.25 mm×100 mm

0.16 mm×125 mm

0.18 mm×125 mm

0.20 mm×125 mm and 0.25 mm×125 mm. Taking the penetrating needling of bilateral Jianyu (LI15)-to-Binao (LI14) and Jianliao (TE14)-to-Binao (LI14) as examples

the practical feasibility of needle insertion was observed. The results showed that when using either the needle-holding insertion with both hands or the sectional tube-guided insertion

all specifications of fine elongated-needles could meet the clinical needling requirements

and all subjects experienced the

deqi

sensation characterized by soreness

numbness

heaviness and distension. The insertion depth of fine elongated-needles increased with the needle length. Compared with the needle-holding insertion with both hands

the sectional tube-guided insertion m

ethod was more capable of painless operation during skin penetration. This study provides a preliminary exploration of the clinical feasibility of needle insertion with the novel comfort fine elongated-needles

summarizes their operational characteristics and limitations

and may offer directions for further clinical validation.