The RT-50+ provides all of the best qualities of the RT-50 with the tonal stability provided by the heavy shell design. The added weight allows more projection of the sound while retaining a dark core of sound. It works really well when very loud dynamics are required but also makes the response easy for soft dynamics.
Specifications:
Cup Diameter: 33mm/1.3in, deep funnel shaped cup
Rim: Width 7.5mm/0.3in, flat rim with sharp inner edge
Bore: 8.3mm/0.33in