RV Tissue Digester, 19 oz - Thetford 15844 [VERSATILITY]: Thetford's Tissue Digester is designed to work with RVs and boats [FUNCTIONALITY]: Breaks up tissue-causing clogs and keeps drain lines clean and flowing free [UTILITY]: Specially formulated to prevents build-ups on tank walls and drain lines [CONVENIENCE]: Formulated to work with grey or black water tanks [SAFETY]: Tissue Digester is 100% biodegradable, safe for all waste treatment systems