Neoprene thickness: 3/2 Zipper: front Long sleeves Long legs The all-rounder with a classic tight fit for all water sports athletes looking for premium features and comfort at a reasonable price. This is our best 3mm suit. Like the Onyx Amp's little brother, the ONYX CORE has a superbly flexible design. Seam Reinforcements All tension points are reinforced and secured from the inside with Melco tape for increased lifespan. Contour Cut To improve flexibility and comfort, all ION wetsuits come with ION Contour Cut. It improves flex at the collar, wrists, elbows, and back of the knees. Drain Holes Whenever two flaps overlap there is a chance that water can accumulate. To combat this, the Onyx core ensures that quick water release is provided when needed, so drain holes are fixed in place from the inside and will not expand. Internal Key Pocket There has been an ongoing discussion if this feature is even necessary, but ION decided to keep it, and it is located on the inside of the suit. ION Men's Wetsuits Size Chart