Keilim25: 6
כַּנֵּי כֵלִים וְהָגְנֵיהֶם, וְאָזְנֵיהֶם, וִידוֹת הַכֵּלִים הַמְקַבְּלִים, שֶׁנָּפְלוּ עֲלֵיהֶן מַשְׁקִין — מְנַגְּבָן וְהֵם טְהוֹרִים. וּשְׁאָר כָּל הַכֵּלִים (שֶׁאֵינָם יְכוֹלִים לְקַבֵּל רִמּוֹנִים) שֶׁאֵין לָהֶם אֲחוֹרַיִם וָתוֹךְ, שֶׁנָּפְלוּ מַשְׁקִין עַל מִקְצָתוֹ — כֻּלּוֹ טָמֵא. כְּלִי שֶׁנִּטְמְאוּ אֲחוֹרָיו בְּמַשְׁקִין — אֲחוֹרָיו טְמֵאִין, תּוֹכוֹ וְאָגְנוֹ וְאָזְנוֹ וְיָדָיו טְהוֹרִין. נִטְמָא תוֹכוֹ — כֻּלּוֹ טָמֵא.
[Regarding] the bases of utensils, and their rims, and their ears, and handles of utensils that can receive, upon which liquids fell, one dries them and they are tahor. But [regarding] all other utensils (that cannot hold pomegranates) which do not have an exterior and an interior, upon a part of which liquids fell, all of it is tamei. [Regarding] a utensil whose exterior was rendered tamei by liquids, its exterior is tamei, [but] its interior, its rim, its ears, and its handles are tahor. [If] its interior became tamei, all of it is tamei.
Keilim25: 7
כָּל הַכֵּלִים יֵשׁ לָהֶן אֲחוֹרַיִם וָתוֹךְ, וְיֵשׁ לָהֶם בֵּית צְבִיעָה. רַבִּי טַרְפוֹן אוֹמֵר: לַעֲרֵבָה גְדוֹלָה שֶׁל עֵץ. רַבִּי עֲקִיבָא אוֹמֵר: לְכוֹסוֹת. רַבִּי מֵאִיר אוֹמֵר: לְיָדַיִם הַטְּמֵאוֹת וְהַטְּהוֹרוֹת. אָמַר רַבִּי יוֹסֵי: לֹא אָמְרוּ אֶלָּא לְיָדַיִם הַטְּהוֹרוֹת בִּלְבַד.
All utensils have an exterior and an interior, and they have a tzeviah place. R’ Tarfon says: [It was said with regard] to a large wooden trough. R’ Akiva says: [It was said with regard] to cups. R’ Meir says: [It was said with regard] to tamei hands and tahor hands. R’ Yose said: [The Sages] stated this ruling only [with regard] to tahor hands.