Durable Envelopes: SUNEE clasp envelopes are made of sturdy 28 lb brown kraft paper. Envelopes Self Seal & Clasp Envelopes in SUNEE. Premium 28 lb Paper ✔ ✔ ✔ ✔ ✔ ✔ ✔. Unit Count 100.00 Count. Weight: 4.11 lb.