One of the few onaholes that gets ultra high marks on both form factor and durability is the Sexy Older Sister from Toys Heart, Japan.
The hole uses a 3D large-diameter spiral structure that twists around your member as you have your way with it. The high-density SafeSkin skin material is secure, but still very soft in your hands, without any of that rubbery latex smell from cheap onaholes.
Sexy Older Sister onahole features:
• 3D spiral structure hole
• Realistic modeling of vagina
• Safe Skin material
• Finishing area for ejaculation
• Length: 150mm (6”)
• Weight: 400g. (0.9lb.)