MORPH-HOLE has an ergo shape designed to fit all around, the plug is shaped to fit right, just deep enough--wider where you want, but narrow where you need so you can grip it in. The inner plug humps the right spot, the inner opening fits toys and more with a larger knob-chamber opens wider with rings and humps for your partners pleasure. It curves to morph into your trench, with crack-stretching thick rim-lips that keeps your gaping wide. From the outside you get an amazing wide, deep funnel base, its super-huge because we KNOW how you use gape-plugs. The wide-mouth base makes filling and lubing deep inside easier, makes crack-stuffing with toys the bestthe neck is narrow enough to clamp down and keep MORPH-HOLE in PLUS+silicone TPR/silicone blend: silicone for a smooth and warm feel, TPR for amazing stretch and strength. Phthalate free. LUBE SAFE: Water-based lube, hybrid or silicone lube, oil-base lubes not recommended. CARE: Wash after use in warm soapy water, air dry. Store toys separately: we recommend storing in breathable cloth pouches or for larger toys, in cotton socks.