Evans Strata 1400 concert bass drum heads feature a single ply of 14mil film with the unique Strata coating that simulates the feel and warmth of sound found with calf skin heads. For over 60 years Evans has been an innovator in drumhead manufacturing and design. As the creator of the first synthetic drumhead and other revolutionary products such as EMAD Hydraulics and the UV1 series Evans drumheads are designed with the intent of solving problems for drummers. Regarded for high quality and consistency all Evans drumheads are made in the USA and feature Level 360 Technology. 36 concert drum head with a single ply of 14mil film Full-bodied sustain and balanced attack Strata coating offers a warmth of tone similar to that of calf skin Lacks the papery sound quality of other synthetic concert bass heads All Evans drum heads are designed engineered and manufactured in the USA