Thera-band Red Slow Deflate System Pro-series Anti-burst Exercise Ball, 55cm by TheraBand

Very satisfied with this exercise ball. Unlike cheaper versions, I've had this for over a month and it hasn't deflated at all. Very heavy-duty and durable - same as the high quality versions used in physical therapy facilities. Definitely worth the money.Note that there are some complaints about the sizes not being accurate. I suspect this is due to people not fully inflating them. You need to inflate it to 80% of the diameter and let it sit for 24 hours so that it can strech out a bit. Then inflate it using the provided 'circumference tape' to inflate it to it's full size. I used a small, portable 12V car air compressor with a pressure gauge. It's deceiving because you think it's fully inflated at ~80% diameter but it will stretch to it's full diameter while staying <10psi.Only minor complaint is that the ball does make some squeaking noise while I use it on a wood floor. Not a surprise, but just something to note.

Better quality then what you find at the store, my physical therapist sold the same brand. Need to have stand up bike pump in order to air it up.

This ball is supposed to be a 55cm 22" ball but it is only 18". It is fully inflated and still only measures 18". This is the same brand that I already have but this ball is mis-marked. It is only a 45cm ball. I have a 65cm 26" ball but wanted to drop down to a 55cm ball for a couple of my home exercises. I use both a 65cm ball and 55cm ball of the exact same brand at the physical therapy center and this is a full size smaller than the 55cm. I am 5'7" so this ball is much too small.

I have been using a thera ball as my office chair since 2000. Love this ball! They last well, just watch out for grit and staples on the floor!

Nothing in box but a deflated ball. No needles for inflating it, no exercise guide. Just the packing slip from Amazon. Not great form, TheraBand.