Better than the Speedo Bubble Cap.  For me, Size Medium is the most comfortable.  Fits snug without feeling tight, and therefore is leakproof and warm in cold weather.  I like this Water Gear model better than any other bubble cap.

I am unable to complete an order.  The options on size and color, etc. are circuitous.  Please help.  I need the medium size water gear bubble swim cap with chin strap in purple, since that's all that is available, and a medium size.

Previously had a Speedo Bubble Cap with Chin Strap, which comes in one size which was a bit big for me but usable.

Ordered, and received within four days, the Water Gear Bubble cap in Medium, which is the same as the Speedo as far as I can tell, except that it is smaller and fits me better.

I like caps with chin straps because they keep the water out of my ears. (Ear plugs do not work for me because of bent ear canals.) Of course, being made of rubber, this type of cap needs replacing regularly.